Naturen 8, 15.4.1893
En tysk fysiker, hr Bibra, har nyligen föreslagit bayerska regeringen att vid tillvärkningen af banksedlar tillämpa följande metod:
Om man delvis neddoppar ett pappersark uti en lösning innehållande flere olika färgämnen, uppsuges hvarje af dem med olika hastighet, och pappret kommer sålunda att förete en af en serie olika färgade band betäkt yta, af hvilka band hvart och ett erhåller en alldeles bestämd färg liksom ock en bestämd bredd. För att förekomma förfalskningar, blefve det då blott nödigt att hemlighålla sammansättningen af den använda färgblandningen.
Man skulle till exempel kunna låta en droppe af färglösningen falla pä midten af ett pappersstycke, och på detta sätt erhålla ett visst antal koncentriska ringar alla af fullständigt bestämd bredd, beroende på beskaffenheten och den relativa mängden af de färgämnen som kommit till användning.
30.7.14
Om ortokromatisk fotografering och dess användning för afbildande af föremål i naturliga färger.
Naturen 8, 15.4.1893
(Föredrag hållet i Fysiska föreningen i Helsingfors den 24 mars 1893)
Af Daniel Nyblin.
Fotografin - konsten att framställa bilder genom ljusets invärkan - är i främsta rummet grundad på vissa silverföreningars egenskap att undergå kemiska och fysikaliska förändringar, när de utsättas för invärkan af ljus.
De silfverföreningar, hvilka funnit den största användning i fotografin, äro klor- brom- och jodsilfver.
Kännedomen om klorsilfrets egenskap att, utsatt för solljus, förändra sin ursprungliga hvita färg till mörk violett är mycket gammal. Redan alkemisterna hade iakttagit detta, och år 1727 gjorde dr Johann Heinrich Schultze försök att framställa ljusbilder medels klorsilfver.
Carl Wilhelm Scheele var den första som närmare studerade denna klorsilfrets egenskap. Han uppvisade år 1775 att denna klorsilfrets färgförändring beror därpå, att det af ljuset reduceras till metalliskt silfver, och att ljusets violetta strålar vid denna process äro
de värksammaste.
Bromsilfver förändrar i ljuset sin färg till mörkgrå, men denna färgförändring försiggår mycket långsammare än klorsilfrets.
Jodsilfver, som framstälts med användande af ett öfverskott af en jodförening, förändrar icke sin färg, om det utsattes för ljus. Vid närvara af oförändradt silfvernitrat förändras däremot jodsilfrets färg från gul till grågrön.
Denna ljusets värkan på klor- brom- och jodsilfver hvarigenom dessa silfverföreningar undergå en synlig kemisk förändring, kallar man ljusets fotokemiska värkan.
Ljuset utöfvar emellertid äfven en osynlig värkan å dessa silfverföreningar, hvilken man till åtskilnad från den förenämda kallar, ljusets fotografiska värkan. Utsättas nämligen klor- brom- eller jodsilfver en mycker kort tid för ljus undergå de ingen för ögat synlig förändring, men behandlas dessa en kort tid belysta silfverföreningar med något reducerande ämne, t. ex. pyrogallussyra, inträder genast en färgning, hvilken är desto intensivare ju längre eller ju starkare ljuset har värkat.
Genom ljusets värkan har antagligen en reduktionsprocess inledts, hvilken jämförelsevis hastigt fortgår under den kemiska invärkan af det använda reduktionsmedlet.
Klorsilfver besitter de starkaste fotokemiska egenskaperna, så att det hastigast reduceras till metalliskt silfver och starkast färgas genom ljusets omedelbara värkan, medan jodsilfver reduceras och färgas svagast. Bromsilfver står midt emellan dessa.
Ljusets fotografiska värkan synes däremot vara en annan. Jodsilfver angripes starkast, bromsilfver därnäst, och klorsilfver svagast; detta dock under förutsättning att s. k. fysikalisk eller sur framkallning användes. Användes däremot s. k. kemisk framkallning, står bromsilfver i främsta rummet såsom det, hvilket starkast reduceras, klorsilfver kommer i andra rummet och jodsilfver reduceras minst.
Det fysikaliska framkallandet består däri, att man medels något reducerande ämne, såsom järnvitriol eller sur pyrogallussyrelösning, ur silfvernitratlösning utfäller metalliskt silfver på de af ljuset påvärkade klor- bromeller jodsilfverföreningarna.
Det kemiska framkallandet består i en reduktion af den genom ljuset förändrade silfverföreningen till metalliskt silfver. Ljusets skilda färgstrålar utöfva en mycket olika värkan på silverföreningarna. Endast ljns som af en silfverförening absorberas, utöfvar på den samma fotografisk värkan.
Detta är orsaken hvarför man ansett vissa strålar fotografiskt värksamma, andra åter fotografiskt ovärksamma. Det är emellertid bevisadt, att man kan göra alla ljusstrålar fotografiskt värksamma, om man kan förmå silfverföreningarna att absorbera de samma. Det gifves tvänne sätt att höja silverföreningarnas känslighet för de ljusstrålar hvilka betraktas såsom icke fotografiskt värksamma.
Det ena sättet är, att genom färgade ljusfiltra absorbera de fotografiskt värksammaste ljusstrålarna - de blå och violetta - innan ljuset kommer i beröring med silfverföreningen.
Den andra metoden är att bringa silfverföreningarna i innerlig beröring med vissa ämnen som absorbera de mindre värksamma strålarna. Sådana i fotografin använda ämnen kallas optiska sensibilatorer.
Erfarenheten hade redan tidigt lärt forskarne på det fotografiska området att jodsilfrets ljuskänslighet blef ända till 20 gånger större, om det i närvara af silfvernitratlösning utsattes för ljus. Silfvernitratets gynsamma värkan som sensibilator för jodsilfver grundar sig på dess förmåga att binda den jod, hvilken frigöres ur jodsilfret, när detta utsattes för ljus. Tannin, gallussyra m, fl. ämnen värka på samma sätt sensibiliserande som silfvernitrat, men deras värkan är betydligt svagare.
Alla de ämnen, hvilka höja silfverföreningarnas känslighet för hvitt ljus, bära den gemensamma benämningen: kemiska sensibilatorer. De höja ljuskänsligheten genom att upptaga jod, klor och brom, men de förändra icke silfverföreningarnas förhållande till spektrums olika färger, d. v. s. de strålar, hvilka af silfverföreningarna starkast absorberas, utöfva den starkaste fotografiska värkan äfven i närvara af kemiska sensibilatorer.
Annorlunda är förhållandet med de optiska sensibilatorerna. Dessa höja icke silfverföreningarnas känslighet för hvitt ljus, utan tvärtom förorsaka de flesta af dem en nedsättning af den totala ljuskänsligheten, men genom absorption af de fotografiskt mindre aktiva ljusstrålarna höja de silfverföreningarnas känslighet för dessa.
Under fotografiska undersökningar af solspektrums värkan på jod- klor- och bromsilfver gjorde prof. Hermann Vogel i Berlin 1873 en upptakt, hvilken blef af genomgripande betydelse för fotografins utveckling.
Vid sina försök använde han bland andra äfven kollodium-torrplåtar af engelsk tillvärkning.
Dessa torrplåtar, hvilkas skikt för erhållande af större ogenomskinlighet var färgadt gult med ett för Vogel okändt färgämne, visade ett egendomligt förhållande till spektrums färger.
Såsom redan nämdt är det företrädesvis de violetta och blå ljusstrålarna, hvilka äro de fotografiskt mest värksamma. Detta gäller för såväl jodsilfver som ock för bromsilfver och klorsilfver. Jodsilfver reduceras af spektrums strålar från ultraviolett till gult, men indigo vid linien G utöfvar på jodsilfver den starkaste värkan. Kurvan F på fig. i framställer grafiskt den värkan spektrums strålar utöfva på s. k. våta kollodiumplåtar, d. v. s. jodsilfver med silfvernitrat. Kurvan visar stark stigning från ultra violett till indigo, där maximum uppnås mellan linierna G och F, hvarefter värkan hastigt aftar till dess den slutligen fullständigt upphör vid linien D.
Rent jodsilfver, sådant detförekommer i jodsilfverkollodiumtorrplåtar utan kemisk sensibilator, visar en värkan sådan kurvan II utvisar. Äfven detta har sitt maximum i indigo, fastän mycket svagare än jodsilfver med silfvernitrat såsom sensibilator.
Kurvan III visar bromsilfrets, kurvan IV åter klorsilfrets känslighet för spektrums olika färgade ljusstrålar. Alla dessa silfverföreningar påvärkas starkast af de violetta eller de blå ljusstrålarna, och alla visa de ett bestämdt känslighetsmaximum.
På helt annat sätt förhöllo sig de omnämda gulfärgade torrplåtarna. Dessa visade tvänne maxima - tvänne ställen där ljuset utöfvade en starkare värkan - såsom kurvan V utvisar. Först och främst framträdde jodsilfrets vanliga känslighet för indigo, men dessutom voro plåtarna starkt känsliga för gulgrönt, ett förhållande som tidigare aldrig iakttagits hos någon fotografisk plåt.
Vogel leddes, som naturligt var, på tanken att orsaken till detta forhållande stod att söka hos det färgämne med hvilket dessa plåtar voro impregnerade.
Han anstälde då försök med andra färgämnen och blef inom kort förvissad om att silverföreningarna kunde göras känsliga äfven för de såsom ovärksamma ansedda ljusstrålarna, ifall de blandades med vissa, färgämnen, hvilka starkt absorbera de ljusstrålar, af hvilka silfverföreningarna endast svagt reduceras.
Härigenom var teorin om absorptionsformågans inflytande på ljusets kemiska och fysikaliska värkningar på silfverföreningarna faststäld.
Det bör framhållas att dessa optiska sensibilatorer icke utöfva någon kemisk värkan på silfverföreningarna. Här föreligger icke någon kemisk förening mellan dessa sensibilatorer och silfverföreningarna, utan endast en homogen, mekanisk blandning. Färgämnet omsluter silfvermolekylerna och tillför dem genom absorbering det ljus, hvilket silfverföreningarna själfva ej absorbera. De optiska sensibilatorernas värkan är altså af rent fysikalisk natur.
Det samma är fallet med de tidigare nämda ljusfiltra. Dessa äro färgade glas hvilka införas mellan det fotografiska objektivet och den ljuskänsliga plåten, eller hvilka anbringas framför prismat i spektrografen och därigenom afhålla de ljusstrålar från att värka, hvilka af ljusfiltrum absorberas.
Genom samtidigt användande af olika färgade ljusfiltra och optiska sensibilatorer kunna de fotografiska plåtarna göras känsliga för hvar och en af de tre hufvudfärgerna och deras kombinationer.
Af optiska sensibilatorer hafva cyanin och eosin funnit den största användning i fotografin. Cyaninets absorptionsband i spektrum sträcker sig från E till mellan D och C (fig. 2), eosinets från F till mellan E och D. En blandning af eosin och cyanin, hvilken kallas azalin, absorberar ljusstrålarna från F till C och visar trenne maxima (kurvan VIII).
Ett annat anmärkningsvärdt förhållande visa dessa optiska sensibilatorer i sin värkan på silfverföreningarnas ljuskänslighet. De höja icke känsligheten mest för det ljus, de själfva starkast absorbera, utan känslighetens maximum förflyttas något längre mot rödt.
Kurvan IX på fig. 2 visar känsligheten hos en bromsilfvergelatinplåt hvilken är färgad med eosin. Den har ett maximum mellan linierna G och F, hvilket är att tillskrifva bromsilfrets egen absorption, samt ett annat mellan linierna E och D, hvilket härrör från eosinet. Det senare maximum är betydligt närmare rödt än eosinets absorptionsband.
Det samma är äfven fallet med bromsilfvergelatinplåtar färgade med cyanin eller med azalin, såsom kurvorna X och XI utvisa.
Af denna orsak är cyanin en utmärkt sensibilator för orange och äfven för rödt, eosin för gult och grönt.
Dessa Vogels upptakter äro af oberäknelig nytta för fotografins utveckling, och de hafva fört fotografin ett lika långt steg framåt som Daguerres upptakt af den osynliga bildens framkallning genom kvicksilfverångor. Isynnerhet har reproduktionsfotografin dragit stor nytta af de optiska sensibilatorerna. Gulnade manuskript och teckningar, hvilka förr knappast kunde fotograferas, och målningar, hvilka endast mycket ofullständigt kunde återges, kunna numera med stor lätthet på ett tillfredsställande sätt reproduceras genom detta nya s, k. ortokromatiska förfaringssätt.
Närstående reproduktioner af tvänne fotografier tagna, den ena (fig. 3) med en vanlig plåt, den andra (fig. 4) med färgkänslig (ortokromatisk) plåt, gifva prof på det nya förfaringssättets stora företräden för återgifvande af färgade föremål. Medan de små mörkvioletta blommorna nederst i buketten af den vanliga plåten visserligen återgifvits med sin riktiga färgvalör, ha de stora ranunkelgula blommorna på denna plåt utfallit alldeles mörka, då de däremot på den ortokromatiska plåten framstå med sin rätta valör, d. v. s. äro alldeles ljusa. Äfven själfva vasen har först på den ortokromatiska plåten erhållit den valör som svarar mot dess ljusgula färg.
Äfven färgtrycket (kromolitografin) kommer genom de optiska sensibilatorerna att helt och hållet förändra natur. Färgtryck, hvilka erfordrat 15 ä 20 för hand utförda tryckplåtar för de olika färgnyanserna, öfverträffas numera af fotografiska färgtryck utförda med endast 3 tryckplåtar.
Stödjande sig på teorin för de optiska sensibilatorerna har prof. Vogel framstält förslag till denna nya färgtrycksmetod, hvilken till sina praktiska detaljer senare utarbetats af hans son, dr E. Vogel jämte litografen hr Ulrich.
Denna tryckmetod kallas naturfärgtryck och utföres på så sätt, att foremålet, som skall afbildas, fotograferas på 3 skilda plåtar:
1. Genom ett blått glas på en vanlig bromsilfverplåt, hvilken såsom tidigare nämdt är starkt ljuskänslig för blå och violetta strålar. Det blåa ljusfiltrum afhåller alla andra färger från att värka på plåten, förutom dem i hvilka blått ingår.
2. Genom ett gult glas på en plåt hvilken är färgad med en sensibilator för gult ljus, t. ex. eosin.
3. Genom ett rödt ljusfiltrum på en för röda strålar känsliggjord plåt (cyanin).
Från dessa negativplåtar framställas trenne tryckplåtar, hvilka tryckas med de tre färgerna rödt, blått och gult, på så sätt att den plåt, som är framstäld med användande af blått glas på ofärgad bromsilfverplåt, tryckes med en röd färg, hvars absorptionsspektrum är möjligast likt bromsilfrets; den, som är tagen genom gult glas, med en färg hvilken så ycket som möjligt liknar eosin, och slutligen den, som är fotograferad genom rödt glas, med en cyaninet liknande färg.
På detta sätt åstadkommes en naturtrogen bild af föremålet i alla dess färgnyanser.
Laterna magica bilder i naturliga färger framställas på liknande sätt, endast med den skilnad att bilderna icke tryckas i färger, utan förstoras alla tre plåtarna på samma gång med tillhjälp af ett tredubbelt skioptikon, i det att man bakom plåtarna anbringar ett glas af motsvarande färg.
Slutligen bör nämnas, att äfven för prof. Lippmanns metod att fotografera spektrum i dess naturliga färger de optiska sensibilatorerna varit af oskattbart värde, ty utan dem skulle det ej lyckats honom att återgifva spektrums mindre brytbara strålar.
(Föredrag hållet i Fysiska föreningen i Helsingfors den 24 mars 1893)
Af Daniel Nyblin.
Fotografin - konsten att framställa bilder genom ljusets invärkan - är i främsta rummet grundad på vissa silverföreningars egenskap att undergå kemiska och fysikaliska förändringar, när de utsättas för invärkan af ljus.
De silfverföreningar, hvilka funnit den största användning i fotografin, äro klor- brom- och jodsilfver.
Kännedomen om klorsilfrets egenskap att, utsatt för solljus, förändra sin ursprungliga hvita färg till mörk violett är mycket gammal. Redan alkemisterna hade iakttagit detta, och år 1727 gjorde dr Johann Heinrich Schultze försök att framställa ljusbilder medels klorsilfver.
Carl Wilhelm Scheele var den första som närmare studerade denna klorsilfrets egenskap. Han uppvisade år 1775 att denna klorsilfrets färgförändring beror därpå, att det af ljuset reduceras till metalliskt silfver, och att ljusets violetta strålar vid denna process äro
de värksammaste.
Bromsilfver förändrar i ljuset sin färg till mörkgrå, men denna färgförändring försiggår mycket långsammare än klorsilfrets.
Jodsilfver, som framstälts med användande af ett öfverskott af en jodförening, förändrar icke sin färg, om det utsattes för ljus. Vid närvara af oförändradt silfvernitrat förändras däremot jodsilfrets färg från gul till grågrön.
Denna ljusets värkan på klor- brom- och jodsilfver hvarigenom dessa silfverföreningar undergå en synlig kemisk förändring, kallar man ljusets fotokemiska värkan.
Ljuset utöfvar emellertid äfven en osynlig värkan å dessa silfverföreningar, hvilken man till åtskilnad från den förenämda kallar, ljusets fotografiska värkan. Utsättas nämligen klor- brom- eller jodsilfver en mycker kort tid för ljus undergå de ingen för ögat synlig förändring, men behandlas dessa en kort tid belysta silfverföreningar med något reducerande ämne, t. ex. pyrogallussyra, inträder genast en färgning, hvilken är desto intensivare ju längre eller ju starkare ljuset har värkat.
Genom ljusets värkan har antagligen en reduktionsprocess inledts, hvilken jämförelsevis hastigt fortgår under den kemiska invärkan af det använda reduktionsmedlet.
Klorsilfver besitter de starkaste fotokemiska egenskaperna, så att det hastigast reduceras till metalliskt silfver och starkast färgas genom ljusets omedelbara värkan, medan jodsilfver reduceras och färgas svagast. Bromsilfver står midt emellan dessa.
Ljusets fotografiska värkan synes däremot vara en annan. Jodsilfver angripes starkast, bromsilfver därnäst, och klorsilfver svagast; detta dock under förutsättning att s. k. fysikalisk eller sur framkallning användes. Användes däremot s. k. kemisk framkallning, står bromsilfver i främsta rummet såsom det, hvilket starkast reduceras, klorsilfver kommer i andra rummet och jodsilfver reduceras minst.
Det fysikaliska framkallandet består däri, att man medels något reducerande ämne, såsom järnvitriol eller sur pyrogallussyrelösning, ur silfvernitratlösning utfäller metalliskt silfver på de af ljuset påvärkade klor- bromeller jodsilfverföreningarna.
Det kemiska framkallandet består i en reduktion af den genom ljuset förändrade silfverföreningen till metalliskt silfver. Ljusets skilda färgstrålar utöfva en mycket olika värkan på silverföreningarna. Endast ljns som af en silfverförening absorberas, utöfvar på den samma fotografisk värkan.
Detta är orsaken hvarför man ansett vissa strålar fotografiskt värksamma, andra åter fotografiskt ovärksamma. Det är emellertid bevisadt, att man kan göra alla ljusstrålar fotografiskt värksamma, om man kan förmå silfverföreningarna att absorbera de samma. Det gifves tvänne sätt att höja silverföreningarnas känslighet för de ljusstrålar hvilka betraktas såsom icke fotografiskt värksamma.
Det ena sättet är, att genom färgade ljusfiltra absorbera de fotografiskt värksammaste ljusstrålarna - de blå och violetta - innan ljuset kommer i beröring med silfverföreningen.
Den andra metoden är att bringa silfverföreningarna i innerlig beröring med vissa ämnen som absorbera de mindre värksamma strålarna. Sådana i fotografin använda ämnen kallas optiska sensibilatorer.
Erfarenheten hade redan tidigt lärt forskarne på det fotografiska området att jodsilfrets ljuskänslighet blef ända till 20 gånger större, om det i närvara af silfvernitratlösning utsattes för ljus. Silfvernitratets gynsamma värkan som sensibilator för jodsilfver grundar sig på dess förmåga att binda den jod, hvilken frigöres ur jodsilfret, när detta utsattes för ljus. Tannin, gallussyra m, fl. ämnen värka på samma sätt sensibiliserande som silfvernitrat, men deras värkan är betydligt svagare.
Alla de ämnen, hvilka höja silfverföreningarnas känslighet för hvitt ljus, bära den gemensamma benämningen: kemiska sensibilatorer. De höja ljuskänsligheten genom att upptaga jod, klor och brom, men de förändra icke silfverföreningarnas förhållande till spektrums olika färger, d. v. s. de strålar, hvilka af silfverföreningarna starkast absorberas, utöfva den starkaste fotografiska värkan äfven i närvara af kemiska sensibilatorer.
Annorlunda är förhållandet med de optiska sensibilatorerna. Dessa höja icke silfverföreningarnas känslighet för hvitt ljus, utan tvärtom förorsaka de flesta af dem en nedsättning af den totala ljuskänsligheten, men genom absorption af de fotografiskt mindre aktiva ljusstrålarna höja de silfverföreningarnas känslighet för dessa.
Under fotografiska undersökningar af solspektrums värkan på jod- klor- och bromsilfver gjorde prof. Hermann Vogel i Berlin 1873 en upptakt, hvilken blef af genomgripande betydelse för fotografins utveckling.
Vid sina försök använde han bland andra äfven kollodium-torrplåtar af engelsk tillvärkning.
Dessa torrplåtar, hvilkas skikt för erhållande af större ogenomskinlighet var färgadt gult med ett för Vogel okändt färgämne, visade ett egendomligt förhållande till spektrums färger.
Såsom redan nämdt är det företrädesvis de violetta och blå ljusstrålarna, hvilka äro de fotografiskt mest värksamma. Detta gäller för såväl jodsilfver som ock för bromsilfver och klorsilfver. Jodsilfver reduceras af spektrums strålar från ultraviolett till gult, men indigo vid linien G utöfvar på jodsilfver den starkaste värkan. Kurvan F på fig. i framställer grafiskt den värkan spektrums strålar utöfva på s. k. våta kollodiumplåtar, d. v. s. jodsilfver med silfvernitrat. Kurvan visar stark stigning från ultra violett till indigo, där maximum uppnås mellan linierna G och F, hvarefter värkan hastigt aftar till dess den slutligen fullständigt upphör vid linien D.
Rent jodsilfver, sådant detförekommer i jodsilfverkollodiumtorrplåtar utan kemisk sensibilator, visar en värkan sådan kurvan II utvisar. Äfven detta har sitt maximum i indigo, fastän mycket svagare än jodsilfver med silfvernitrat såsom sensibilator.
Kurvan III visar bromsilfrets, kurvan IV åter klorsilfrets känslighet för spektrums olika färgade ljusstrålar. Alla dessa silfverföreningar påvärkas starkast af de violetta eller de blå ljusstrålarna, och alla visa de ett bestämdt känslighetsmaximum.
På helt annat sätt förhöllo sig de omnämda gulfärgade torrplåtarna. Dessa visade tvänne maxima - tvänne ställen där ljuset utöfvade en starkare värkan - såsom kurvan V utvisar. Först och främst framträdde jodsilfrets vanliga känslighet för indigo, men dessutom voro plåtarna starkt känsliga för gulgrönt, ett förhållande som tidigare aldrig iakttagits hos någon fotografisk plåt.
Vogel leddes, som naturligt var, på tanken att orsaken till detta forhållande stod att söka hos det färgämne med hvilket dessa plåtar voro impregnerade.
Han anstälde då försök med andra färgämnen och blef inom kort förvissad om att silverföreningarna kunde göras känsliga äfven för de såsom ovärksamma ansedda ljusstrålarna, ifall de blandades med vissa, färgämnen, hvilka starkt absorbera de ljusstrålar, af hvilka silfverföreningarna endast svagt reduceras.
Härigenom var teorin om absorptionsformågans inflytande på ljusets kemiska och fysikaliska värkningar på silfverföreningarna faststäld.
Det bör framhållas att dessa optiska sensibilatorer icke utöfva någon kemisk värkan på silfverföreningarna. Här föreligger icke någon kemisk förening mellan dessa sensibilatorer och silfverföreningarna, utan endast en homogen, mekanisk blandning. Färgämnet omsluter silfvermolekylerna och tillför dem genom absorbering det ljus, hvilket silfverföreningarna själfva ej absorbera. De optiska sensibilatorernas värkan är altså af rent fysikalisk natur.
Det samma är fallet med de tidigare nämda ljusfiltra. Dessa äro färgade glas hvilka införas mellan det fotografiska objektivet och den ljuskänsliga plåten, eller hvilka anbringas framför prismat i spektrografen och därigenom afhålla de ljusstrålar från att värka, hvilka af ljusfiltrum absorberas.
Genom samtidigt användande af olika färgade ljusfiltra och optiska sensibilatorer kunna de fotografiska plåtarna göras känsliga för hvar och en af de tre hufvudfärgerna och deras kombinationer.
Af optiska sensibilatorer hafva cyanin och eosin funnit den största användning i fotografin. Cyaninets absorptionsband i spektrum sträcker sig från E till mellan D och C (fig. 2), eosinets från F till mellan E och D. En blandning af eosin och cyanin, hvilken kallas azalin, absorberar ljusstrålarna från F till C och visar trenne maxima (kurvan VIII).
Ett annat anmärkningsvärdt förhållande visa dessa optiska sensibilatorer i sin värkan på silfverföreningarnas ljuskänslighet. De höja icke känsligheten mest för det ljus, de själfva starkast absorbera, utan känslighetens maximum förflyttas något längre mot rödt.
Kurvan IX på fig. 2 visar känsligheten hos en bromsilfvergelatinplåt hvilken är färgad med eosin. Den har ett maximum mellan linierna G och F, hvilket är att tillskrifva bromsilfrets egen absorption, samt ett annat mellan linierna E och D, hvilket härrör från eosinet. Det senare maximum är betydligt närmare rödt än eosinets absorptionsband.
Det samma är äfven fallet med bromsilfvergelatinplåtar färgade med cyanin eller med azalin, såsom kurvorna X och XI utvisa.
Af denna orsak är cyanin en utmärkt sensibilator för orange och äfven för rödt, eosin för gult och grönt.
Dessa Vogels upptakter äro af oberäknelig nytta för fotografins utveckling, och de hafva fört fotografin ett lika långt steg framåt som Daguerres upptakt af den osynliga bildens framkallning genom kvicksilfverångor. Isynnerhet har reproduktionsfotografin dragit stor nytta af de optiska sensibilatorerna. Gulnade manuskript och teckningar, hvilka förr knappast kunde fotograferas, och målningar, hvilka endast mycket ofullständigt kunde återges, kunna numera med stor lätthet på ett tillfredsställande sätt reproduceras genom detta nya s, k. ortokromatiska förfaringssätt.
Närstående reproduktioner af tvänne fotografier tagna, den ena (fig. 3) med en vanlig plåt, den andra (fig. 4) med färgkänslig (ortokromatisk) plåt, gifva prof på det nya förfaringssättets stora företräden för återgifvande af färgade föremål. Medan de små mörkvioletta blommorna nederst i buketten af den vanliga plåten visserligen återgifvits med sin riktiga färgvalör, ha de stora ranunkelgula blommorna på denna plåt utfallit alldeles mörka, då de däremot på den ortokromatiska plåten framstå med sin rätta valör, d. v. s. äro alldeles ljusa. Äfven själfva vasen har först på den ortokromatiska plåten erhållit den valör som svarar mot dess ljusgula färg.
Äfven färgtrycket (kromolitografin) kommer genom de optiska sensibilatorerna att helt och hållet förändra natur. Färgtryck, hvilka erfordrat 15 ä 20 för hand utförda tryckplåtar för de olika färgnyanserna, öfverträffas numera af fotografiska färgtryck utförda med endast 3 tryckplåtar.
Stödjande sig på teorin för de optiska sensibilatorerna har prof. Vogel framstält förslag till denna nya färgtrycksmetod, hvilken till sina praktiska detaljer senare utarbetats af hans son, dr E. Vogel jämte litografen hr Ulrich.
Denna tryckmetod kallas naturfärgtryck och utföres på så sätt, att foremålet, som skall afbildas, fotograferas på 3 skilda plåtar:
1. Genom ett blått glas på en vanlig bromsilfverplåt, hvilken såsom tidigare nämdt är starkt ljuskänslig för blå och violetta strålar. Det blåa ljusfiltrum afhåller alla andra färger från att värka på plåten, förutom dem i hvilka blått ingår.
2. Genom ett gult glas på en plåt hvilken är färgad med en sensibilator för gult ljus, t. ex. eosin.
3. Genom ett rödt ljusfiltrum på en för röda strålar känsliggjord plåt (cyanin).
Från dessa negativplåtar framställas trenne tryckplåtar, hvilka tryckas med de tre färgerna rödt, blått och gult, på så sätt att den plåt, som är framstäld med användande af blått glas på ofärgad bromsilfverplåt, tryckes med en röd färg, hvars absorptionsspektrum är möjligast likt bromsilfrets; den, som är tagen genom gult glas, med en färg hvilken så ycket som möjligt liknar eosin, och slutligen den, som är fotograferad genom rödt glas, med en cyaninet liknande färg.
På detta sätt åstadkommes en naturtrogen bild af föremålet i alla dess färgnyanser.
Laterna magica bilder i naturliga färger framställas på liknande sätt, endast med den skilnad att bilderna icke tryckas i färger, utan förstoras alla tre plåtarna på samma gång med tillhjälp af ett tredubbelt skioptikon, i det att man bakom plåtarna anbringar ett glas af motsvarande färg.
Slutligen bör nämnas, att äfven för prof. Lippmanns metod att fotografera spektrum i dess naturliga färger de optiska sensibilatorerna varit af oskattbart värde, ty utan dem skulle det ej lyckats honom att återgifva spektrums mindre brytbara strålar.
29.7.14
28.7.14
27.7.14
Neuwo willojen menettämisestä.
Sanomia Tampereelta 26, 25.6.1866
Meillä oli wiimes wuonna Turuun Sanomissa lähetetty neuwo miten willoja pestään ja niiden kanssa menetetään, että ne tulisiwat semmoisiksi kuin hyödyllinen on. Ehkä sitä kaikki ei hawainneet - elikkä ei enää muista, niin tahdomme taas tässä omassa Sanomassa kertoa: "Tampereen wanha willa-kehru tehdas" saa täten muistuttaa Yleisöä ja erittäinkin niitä, jotka tuowat willoja tehtaaseen kehrättäwäksi, että willoja pestessä eiwät rutista ja wanuta niitä niin että ne kuiwana owat enemmän huowan kappalten kuin willan näköisiä. Sillä lailla walmistetuista willoista ei loskaan saada tasasta ja wahwaa lankaa, waan täytyy willat ennen kehräystä ikään kuinn jauhaa pieniksi, joten nilden luonnollinen pituus haaskataan. Muutamat taitawat ajatella että kyllä tehtaassa niistäkin lankaa saadaan, ja en minä kuitenkaan omista willoistani saa, waan kaikki sekotetaan ja kun ne menewät toisen myötä, jonka on parempia, niin saan minä sitenkin parempia eli hywiä lankoja, josta syntyy huolimattomuus ja se taas muuttuu tawaksi. Allekirjoittaneen willa-kehru tehdas, joka juuri on aiwottu langan kehräykseksi yhteiselle kansalle ja sen wuoksi warustettu isommilla ja wähemmillä koneilla wähempiä ja eri willalaija warten, saa wakuuttaa että samoista willoista, kun tuodaan saadaan lanhat, tuotakoon niitä sitten 3, 5 eli 10 naulaa j. n. e., ja tahdon aina ahkeroita saawuttaa itselleni kunniaa ja hyödyttää niitä, jotka jotakin tuowat kehrättäwäkseni. Seuraawa tapa meidän tawallisten willain pesemisessä on soweliain: padassa eli kattilassa sulatetaan wedessä suolaa (suolalaukkaa) eli hienomille willalajille soodaa niin paljon että wesi sormissa tuntuu liukkaaksi ja lämmitetään niin lämpimäksi kuin käsi sallii eli noin 50 asteesen, ei lämpeemmäksi, sillä siitä willat tulewat karheiksi ja raswa keittyy kiinni niin ettei sitä sitten millään lailla saada pois, eikä wäri aineet woi niihin enää oikeen kiintyä. Sitte kaadetaan tätä suolawettä willain päälle saawissa ilman rutistamista ja hieromista ja pidetään ½ eli 3/4 tunniksi; willat otetaan sitte ulos niin pikaisesti kuin suinkin mahdollista hautouksesta ja lasketaan koriin (koppaan) joutusasti ja wielä lämpimänä puhtaaseen weteen, kylmään etenkin juoksemaan weteen, puhtaaksi wirutettawiksi, (jota kylmempää wesi on, sitä walkosemmiksi willat tulewat). Sitte otetaan ne ylös rutistamata ja wäantämätä ja paunaan kuiwuun. Tällä tawalla tulewat willat kerliöiksi ja selwiksi, ja siitä saadaan hywiä ja kelwollisia lankoja, joten myös langat walkaistessa tulemat walkoisia.Lyhykäisesti saan tässä myös ilmoittaa, että hinta lankain kehräyksestä on tästä ettei päin seuraawa: pestyistä walkosista willoista 45 penniä, harmaista 47 penniä [], pesemättömistä walkoisista 48 pennia walmiista lankanaulasta, 2 eli 3 kertaisista walkoisista peitto eli sukka langoista 60 pennia. Wärjattyin willain kehrupalkka 50 penniä [] , niin myös waihetetaan puhtaaksi pestyillä willoilla walmilta lankoja 48 pen. wälirahalla walkolsista ja 50 penn. harmaista. Sekä myydään walaistutta ja walkasemattomia puoliwillasia flanellia, walkosia, sinisiä ja lampaan-harmaita lankoja 3 markkaa naulalta ja isommissa osissa alennetuilla hinnoilla, walaistuita ja walkasemattomia kerratuita sopiwia sekä sukka että huiwi langaksi, moniin erinäisiin hintoihin. Tampereelta, kesäkuuta 1866.
Tli. Peterson.
Meillä oli wiimes wuonna Turuun Sanomissa lähetetty neuwo miten willoja pestään ja niiden kanssa menetetään, että ne tulisiwat semmoisiksi kuin hyödyllinen on. Ehkä sitä kaikki ei hawainneet - elikkä ei enää muista, niin tahdomme taas tässä omassa Sanomassa kertoa: "Tampereen wanha willa-kehru tehdas" saa täten muistuttaa Yleisöä ja erittäinkin niitä, jotka tuowat willoja tehtaaseen kehrättäwäksi, että willoja pestessä eiwät rutista ja wanuta niitä niin että ne kuiwana owat enemmän huowan kappalten kuin willan näköisiä. Sillä lailla walmistetuista willoista ei loskaan saada tasasta ja wahwaa lankaa, waan täytyy willat ennen kehräystä ikään kuinn jauhaa pieniksi, joten nilden luonnollinen pituus haaskataan. Muutamat taitawat ajatella että kyllä tehtaassa niistäkin lankaa saadaan, ja en minä kuitenkaan omista willoistani saa, waan kaikki sekotetaan ja kun ne menewät toisen myötä, jonka on parempia, niin saan minä sitenkin parempia eli hywiä lankoja, josta syntyy huolimattomuus ja se taas muuttuu tawaksi. Allekirjoittaneen willa-kehru tehdas, joka juuri on aiwottu langan kehräykseksi yhteiselle kansalle ja sen wuoksi warustettu isommilla ja wähemmillä koneilla wähempiä ja eri willalaija warten, saa wakuuttaa että samoista willoista, kun tuodaan saadaan lanhat, tuotakoon niitä sitten 3, 5 eli 10 naulaa j. n. e., ja tahdon aina ahkeroita saawuttaa itselleni kunniaa ja hyödyttää niitä, jotka jotakin tuowat kehrättäwäkseni. Seuraawa tapa meidän tawallisten willain pesemisessä on soweliain: padassa eli kattilassa sulatetaan wedessä suolaa (suolalaukkaa) eli hienomille willalajille soodaa niin paljon että wesi sormissa tuntuu liukkaaksi ja lämmitetään niin lämpimäksi kuin käsi sallii eli noin 50 asteesen, ei lämpeemmäksi, sillä siitä willat tulewat karheiksi ja raswa keittyy kiinni niin ettei sitä sitten millään lailla saada pois, eikä wäri aineet woi niihin enää oikeen kiintyä. Sitte kaadetaan tätä suolawettä willain päälle saawissa ilman rutistamista ja hieromista ja pidetään ½ eli 3/4 tunniksi; willat otetaan sitte ulos niin pikaisesti kuin suinkin mahdollista hautouksesta ja lasketaan koriin (koppaan) joutusasti ja wielä lämpimänä puhtaaseen weteen, kylmään etenkin juoksemaan weteen, puhtaaksi wirutettawiksi, (jota kylmempää wesi on, sitä walkosemmiksi willat tulewat). Sitte otetaan ne ylös rutistamata ja wäantämätä ja paunaan kuiwuun. Tällä tawalla tulewat willat kerliöiksi ja selwiksi, ja siitä saadaan hywiä ja kelwollisia lankoja, joten myös langat walkaistessa tulemat walkoisia.Lyhykäisesti saan tässä myös ilmoittaa, että hinta lankain kehräyksestä on tästä ettei päin seuraawa: pestyistä walkosista willoista 45 penniä, harmaista 47 penniä [], pesemättömistä walkoisista 48 pennia walmiista lankanaulasta, 2 eli 3 kertaisista walkoisista peitto eli sukka langoista 60 pennia. Wärjattyin willain kehrupalkka 50 penniä [] , niin myös waihetetaan puhtaaksi pestyillä willoilla walmilta lankoja 48 pen. wälirahalla walkolsista ja 50 penn. harmaista. Sekä myydään walaistutta ja walkasemattomia puoliwillasia flanellia, walkosia, sinisiä ja lampaan-harmaita lankoja 3 markkaa naulalta ja isommissa osissa alennetuilla hinnoilla, walaistuita ja walkasemattomia kerratuita sopiwia sekä sukka että huiwi langaksi, moniin erinäisiin hintoihin. Tampereelta, kesäkuuta 1866.
Tli. Peterson.
26.7.14
Oil-Colors Upon Silk or Satin.
Scribners monthly 3, 1881
In using oil paints with silk or satin, begin by squeezing out the tube colors on blotting-paper, which will absorb the oil in the paint and prevent a stain upon the material. Lay ox-gall over the design you have drawn or transferred, before applying the paint. Then charge your brush with the highest general tone of color, and accomplish what you can with a single sweep, taken, if possible, parallel to the rib of the silk, not across the woof. A second application of color should supply the shading; a third, the deepest shadows, For blending colors use only the palette-knife upon the palette. Do not attempt this with your brush upon the silk or staing. Cake-Magnesia, rubbed on the wrong side of the material, is said to be useful in absorbing oil. It can easily be bruised off when the paint is dry.
In using oil paints with silk or satin, begin by squeezing out the tube colors on blotting-paper, which will absorb the oil in the paint and prevent a stain upon the material. Lay ox-gall over the design you have drawn or transferred, before applying the paint. Then charge your brush with the highest general tone of color, and accomplish what you can with a single sweep, taken, if possible, parallel to the rib of the silk, not across the woof. A second application of color should supply the shading; a third, the deepest shadows, For blending colors use only the palette-knife upon the palette. Do not attempt this with your brush upon the silk or staing. Cake-Magnesia, rubbed on the wrong side of the material, is said to be useful in absorbing oil. It can easily be bruised off when the paint is dry.
25.7.14
Punaisesta lumesta ja epäluulosta.*)
Tapio 19, 11.5.1861
*) Tätä kirjoittaan siitä syystä, kuin Karjalan puolella on tänä wuonna satanut punaista lunta josta on monen muotoisia ihmetyön- ja aawitus-tuumia herännyt.Epäluulo ja tietämättömyys näkee usein ihan luonnollisissa tapauksissa jotakin ihmetyötä, ja aawistaa siitä kaikenlaisia pahoja tai hywiä kohtauksia. Silloin pitäisi muka aina jonkun erinomaisen hengen tahi woiman oleman liikkeillä. Mutta tarkemmin luonnon asioita tutkiwa, hawaitsee näissä kummastuttawissa sattumisissa tykkönään luonnollisen menon ja nämät kummitukset muuttuwat ihan selwiksi ja yksinkertaisiksi seikoiksi, joilla on yhtä luonnollinen kuin yksinkertainen perustuksensa.
Muistutamme tällä kertaa waan jokapäiwäisistä asioista. Millä silmillä ei äkkinäinen katso höyrylaiwan kulkua ja mielellään näkisi siinäki jotakin ihmettä, jos hä nei warmaan tietäisi niin aluksen rakennuksen kuin masiinan laittamisen olewan ihmisten työtä. Tämä ihme ja kumma on toki perinpohjin niin yksinkertaista, että poikanulikka Englannissa, oikein tarkasteltuaan kuinka kansi ei tahdo pysyä kiehuwan padan päällä kuin höyryn woima kohottaa sitä sieltä, käytti sitä samaa woimaa ensimmäiseen höyry masiinaan. Luonnon tapauksista on melkein aina pyrstötähtiin tahi komeettain ilmestymistä pidetty sodan tahi muun metelin aawistajana; mutta owathan nämät yhtä tasasesti liikkuwia taiwaankappaleita kuin kuu ja meidän maapallokin, joilla kaikilla on määrätty ja oppineilta jo laskettu kulkunsa, jonka he woiwat ihan sekunnille määrätä ja jota kyllä ainakkaki kuun ja auringon pimenemisissä osoittaa.
Lumen punertuminen taas ei ole paljo ihmeenpätä waan wihertämistä kewäillä, ja sitä wähemmin tämmöinen tapaus woipi olla minkään ennustajana. Ilmassa löytyy nimittäin aina ääretön paljous pieniä kaswuin siemeniä, mutta nämät owat niin tuiki pieniä että niitä ainoastaan isoimmilla suurennuslasilla ja tuskin niilläkään woidaan nähdä. Kuin nämät saawat märkyyttä tarpeheksi ja muuten tulewat heidän itämiselle sopiwaan tilaisuuteen, niin kaswawat äkkiä ihmettelewään paljouteen. Tämän kaswamisen woipi siitäki keksiä, jos katselee kuinka syksypuolella kesää lämpimän sateen jälkeen lukemattomia sieniä sikiää wälistä tunnin ja wähemmänkin ajan sisään. Tämmöistä on Punasen lumenkin laita. Jos panemme hiukan tätä punerrusainetta isonnuslasin alle, niin hawaitsennne tämän punasen ei olewan muuta kuin sangen pieniä kaswuja ja nekin hywin yksinkertaisesta muodosta; ainoastaan waan pieniä punaisia rakkoja, toinen toisensa wieressä. Nämät pikkuiset kaswut kaswawat hywin pikaisesti lumella, joka siitä saapi punertawan näkönsä. Tämmöistä punasta lunta on usein tawattu Pohjois-Amerikassa ja Siperiassakin.
Ennen paawin aikaan, ja ehkä wielä nytkin, sattui wälistä että rippileiwälle ilmestyi tämän kaltaisia punaisia kaswuja jotka tekiwät sen päältäpäin ihan kuin werellä kastelluksi. Mutta tästäpä Papeille ja munkkiloille hätä, kuin muka ihmisten synnstä rippileipä wertyi, ja paikalla ennustiwat siitä jotakin suurta kostoa ja onnettomuutta. Papit pauhaamaan kansalle ja rukoilemaan pyhiä kuwiaan tämän suuren odotetun onnettomuuden estämiseksi. Ja jos ei nyt mitään erinomaista tapahtunut, niin kaikki kansa uskoi pappein rukoustensa ja pyhiin kuwiin kautta poistaneen maailman menehtymistä ja heille siitä kannettiin kosolta kiitos-uhria.
Wälistä tuo myös tapahtuu että lumi on mustana ja monasti tämä seikka on hämmästyttänyt maakansaa meillä. Tämä lumen outo näkö taas tulee pieuistä mustista eläimistä, joita akin sikiää niin mahdottoman paljon että lumi niistä ihankuin mustuu. Näistä seikoistaki näette ettei mitään luounossa tapahdu, jolla ei olisi luonollista perustusta, kuin waan asiata oikein ja tarkoin tutkitaan. Tällä tawalla ihmeet ja muut kummitukset tulewat ihan selwiksi ja luonnollisiksi asioiksi ja kaikki epäluulo waikenee.
E. N.
*) Tätä kirjoittaan siitä syystä, kuin Karjalan puolella on tänä wuonna satanut punaista lunta josta on monen muotoisia ihmetyön- ja aawitus-tuumia herännyt.Epäluulo ja tietämättömyys näkee usein ihan luonnollisissa tapauksissa jotakin ihmetyötä, ja aawistaa siitä kaikenlaisia pahoja tai hywiä kohtauksia. Silloin pitäisi muka aina jonkun erinomaisen hengen tahi woiman oleman liikkeillä. Mutta tarkemmin luonnon asioita tutkiwa, hawaitsee näissä kummastuttawissa sattumisissa tykkönään luonnollisen menon ja nämät kummitukset muuttuwat ihan selwiksi ja yksinkertaisiksi seikoiksi, joilla on yhtä luonnollinen kuin yksinkertainen perustuksensa.
Muistutamme tällä kertaa waan jokapäiwäisistä asioista. Millä silmillä ei äkkinäinen katso höyrylaiwan kulkua ja mielellään näkisi siinäki jotakin ihmettä, jos hä nei warmaan tietäisi niin aluksen rakennuksen kuin masiinan laittamisen olewan ihmisten työtä. Tämä ihme ja kumma on toki perinpohjin niin yksinkertaista, että poikanulikka Englannissa, oikein tarkasteltuaan kuinka kansi ei tahdo pysyä kiehuwan padan päällä kuin höyryn woima kohottaa sitä sieltä, käytti sitä samaa woimaa ensimmäiseen höyry masiinaan. Luonnon tapauksista on melkein aina pyrstötähtiin tahi komeettain ilmestymistä pidetty sodan tahi muun metelin aawistajana; mutta owathan nämät yhtä tasasesti liikkuwia taiwaankappaleita kuin kuu ja meidän maapallokin, joilla kaikilla on määrätty ja oppineilta jo laskettu kulkunsa, jonka he woiwat ihan sekunnille määrätä ja jota kyllä ainakkaki kuun ja auringon pimenemisissä osoittaa.
Lumen punertuminen taas ei ole paljo ihmeenpätä waan wihertämistä kewäillä, ja sitä wähemmin tämmöinen tapaus woipi olla minkään ennustajana. Ilmassa löytyy nimittäin aina ääretön paljous pieniä kaswuin siemeniä, mutta nämät owat niin tuiki pieniä että niitä ainoastaan isoimmilla suurennuslasilla ja tuskin niilläkään woidaan nähdä. Kuin nämät saawat märkyyttä tarpeheksi ja muuten tulewat heidän itämiselle sopiwaan tilaisuuteen, niin kaswawat äkkiä ihmettelewään paljouteen. Tämän kaswamisen woipi siitäki keksiä, jos katselee kuinka syksypuolella kesää lämpimän sateen jälkeen lukemattomia sieniä sikiää wälistä tunnin ja wähemmänkin ajan sisään. Tämmöistä on Punasen lumenkin laita. Jos panemme hiukan tätä punerrusainetta isonnuslasin alle, niin hawaitsennne tämän punasen ei olewan muuta kuin sangen pieniä kaswuja ja nekin hywin yksinkertaisesta muodosta; ainoastaan waan pieniä punaisia rakkoja, toinen toisensa wieressä. Nämät pikkuiset kaswut kaswawat hywin pikaisesti lumella, joka siitä saapi punertawan näkönsä. Tämmöistä punasta lunta on usein tawattu Pohjois-Amerikassa ja Siperiassakin.
Ennen paawin aikaan, ja ehkä wielä nytkin, sattui wälistä että rippileiwälle ilmestyi tämän kaltaisia punaisia kaswuja jotka tekiwät sen päältäpäin ihan kuin werellä kastelluksi. Mutta tästäpä Papeille ja munkkiloille hätä, kuin muka ihmisten synnstä rippileipä wertyi, ja paikalla ennustiwat siitä jotakin suurta kostoa ja onnettomuutta. Papit pauhaamaan kansalle ja rukoilemaan pyhiä kuwiaan tämän suuren odotetun onnettomuuden estämiseksi. Ja jos ei nyt mitään erinomaista tapahtunut, niin kaikki kansa uskoi pappein rukoustensa ja pyhiin kuwiin kautta poistaneen maailman menehtymistä ja heille siitä kannettiin kosolta kiitos-uhria.
Wälistä tuo myös tapahtuu että lumi on mustana ja monasti tämä seikka on hämmästyttänyt maakansaa meillä. Tämä lumen outo näkö taas tulee pieuistä mustista eläimistä, joita akin sikiää niin mahdottoman paljon että lumi niistä ihankuin mustuu. Näistä seikoistaki näette ettei mitään luounossa tapahdu, jolla ei olisi luonollista perustusta, kuin waan asiata oikein ja tarkoin tutkitaan. Tällä tawalla ihmeet ja muut kummitukset tulewat ihan selwiksi ja luonnollisiksi asioiksi ja kaikki epäluulo waikenee.
E. N.
24.7.14
23.7.14
22.7.14
21.7.14
Kasvinimiä.
Luonnon ystävä 4, 1909
a. keräili Kuhmoisista kesällä 1909 Anna Hagelin.
Achillea millefolium, pientarekukka. - Kukista keitetään "makiaa kahvia" lääkkeeksi.
Alenemilla vulgaris, ruusuruoho. - Lehdet hauteena verenmyrkytykseen ja hammastautiin.
Alopecurus ja Phleum, timotei.
Andromeda polifolia, punanen suopursu.
Anemone hepatica, kylmänkukka, vilukukka.
Antennaria dioica, kissankäppä, kissan käpälä.
Artemisia absinthium, koiruoho. - Lääkkeenä.
A. vulgaris, hepohäntä. - "Sen lehdillä haudotaan saunalauteilla kipeitä paikkoja ruumiissa".
Aquilegia vulgaris, kirppa, akleija.
Brassica napus, lanttu.
Campanula, kellokukka.
Calluna vulgaris, kanerva.
Calendula, enkerlummi.
Caltha palustris, sammakonkukka.
Carum carvi, kumina.
Centaurea cyanus, ruiskukka.
Chenopodium album, saviheinä, savikka.
Chaerophyllum silvestre, koiranputki, putkenkukka.
Chrysanthemum leucanthemum, vuohensilmä.
Cirsium heterophyllum, lääväke.
Convallaria majalis, lehmänkielenkukka.
C. polygonatum, harakanvarvas.
Comarum palustre, vesiapila.
Epilobium angustifolium, horsu, horsma.
Equisetum arvense, äijänparta.
Eriophorum polystachium, luippuheinä, niitynnuppuheinä.
E. vaginatum, miekkaheinä.
Fumaria officinalis, peltorassi.
Galeopsis versicolor, peltopeiponen.
Geranium silvaticum, variksenkukka.
Geum rivale, ruumiinsilmänkukka.
Gymnadenia, käärmeenkiekukukka.
Lathyrus pratensis, keltanätky.
L. vernus, kurjenkukka.
Ledum palustre, suopursu. - Siitä keitettyä lääkettä juodaan keuhkotautiin.
Linnaea borealis, kiimaruoho, jäsenheinä. - Saadaan lääkettä jäsentautiin.
Lychnis viscaria, tervakukka.
Lycopodium, katinlieko.
Majanthemum bifolium, lampaankielenkukka.
Matricaria discoidea, saunamaija - lääkettä vatsatauteihin.
Melampyrum, maitoheinä.
Myosotis, lemmenkukka.
Orchis macutata, Jeesuksen kämmenkukka, myös: käärmeenkiekukukka.
Oxalis acetosella, ketunleipä.
Papaver somniferum, palmu.
Paris quadrifolia, harakanmarja.
Plantago major, rautalehti.
Polypodium vulgäre, kivenimeläinen.
Polystichum ja Pteris, sananjalka.
Potentilla tormentilla, järvänänjuuri. - Juuri hienonnetaan, pannaan viinaan ja juodaan sydäntautia vastaan.
Ranunculus acris ja repens, voikukka.
Raphanus raphanistrum, koirannauris.
Rhamnus frangula, taikinapuu.
Rhinanthus, tasku.
Rosa cinnamomea, orjantappura.
Rubus chamaemorus, muurain.
R. arcticus, maarain.
R. idaeus, vattu.
R. saxatilis, hillikka.
Rumex acetosa ja acetosella, suolakka.
R. domestica, tulikukka.
Sedum acre, maksaruoho.
S. telephium, posliinikukka.
Spiraea ulmaria, ankeriaankukka.
Steltaria media, ves'heinä.
S graminea, täht'heinä.
Syringa vulgaris, syreeni.
Tanacetum vulgäre, nappikukka.
Taraxacum officinale, siansilmä.
Thlaspi arvense, taskuheinä.
Trifolium, apilaankukka.
Trientalis europaea, hirsollinkukka.
Urtica dioica, nokkonen.
U. urens, viholainen.
Vaccinium uliginosum, juovikka.
V. oxycoccus, karpale.
Veronica chamaedrys, metsäminttu.
Viburnum opulus, koiranhöyspuu.
Vicia cracca, hiirennätky, hiirenherne.
Viola canina, äienkukka.
V. tricolor, äienkukka, orvonkukka.
----
b. keräili Sodankylästä kesällä 1909 V. W Westerlund.
Achillea millefolium, Pietarin ruoho. - Pantiin ennen tupakan sekaan.
Aira caespitosa, sääriheinä.
Calluna vulgaris, palokanerva.
Cetraria islandica.lislannin jäkälä. - Ennen keitettiin siitä ja jauhoista liisteriä.
Comarum palustre, kurjenpolvi.
Daphne mezereum, näsenimarja, riisimarja. - Käytetään lääkekasvina sekä sisällisesti että ulkonaisesti. Marjoista tehdään riisivoidetta, jota käytetään syöpää vastaan ihmisessä. Jos riisivoide nostaa ihon, niin sitten on syöpätautiin sairastunut ja lääke sen parantaa. Tällä voidellaan 3:na (alikuun?) tuorstaina ja pannaan tukko päälle. Jos nainen, ennenkuin hän synnyttää, vähitellen ottaa sisällisesti kolme yhdeksää näsenimarjaa, niin lapsi ei voi sairastua syöpätautiin. Jos päätä kolottaa, voidellaan otsa ja korvantaukset ja pannaan tukkopäälle.
Voidetta tehdään näin:
1. kolme yhdeksää marjaa, voita, tulikiveä, tervaa tai männyn pihkaa sekoitetaan.
2. kolme yhdeksää marjaa tehdään pulveriksi, tupakkia purraan ja syljetään siihen.
Equisetum sylvaticum, karvakorte.
E. hiemale, rautakorte. - Poleerataan puuta ja rautaa.
Galeopsis versicolor, nukluvainen.
Hierohloe{?), hajuheinä.
Juncus, sältinki.
Ledum palustre, kanerva. - Kun se kukkii, on kontiolla kiima-aika.
Lycopodium selago, riisiruoho. - Lääkekasvi. Kasvi keitetään maidon kanssa, ja keitto otetaan sisällisesti syöpää ja riisitautia vastaan. Lääke panee ensin huonoksi (oksentamaan), mutta sitten seuraa parantuminen. Terveelle ihmiselle ei lääke vaikuta mitään. Jos se on aijottu miehille, otetaan semmoinen riisiruoho, jossa on kolme haaraa (tähkää), vaimolle tai lapsille kaksihaarainen.
Melampyrum, nipla. - Lehmien herkku.
Menyanthes trifoliata, raake.
Polygonum aviculare, paskaheinä.
Potamogeton natans, koirankielirikka.
Ranunculus repens, voikukka.
Rumex domesticus, suolahorma.
Silene inflata, kukkaro.
Solidago virgaurea, pyynkaali.
Sparganium, limarikka.
Spiraea uimaria, angerva. - Heinänteko alkaa, kun se kukkii.
Veronica longifolia, palo- tai keltahorma.
Viola (palustris?), kilpukka.
a. keräili Kuhmoisista kesällä 1909 Anna Hagelin.
Achillea millefolium, pientarekukka. - Kukista keitetään "makiaa kahvia" lääkkeeksi.
Alenemilla vulgaris, ruusuruoho. - Lehdet hauteena verenmyrkytykseen ja hammastautiin.
Alopecurus ja Phleum, timotei.
Andromeda polifolia, punanen suopursu.
Anemone hepatica, kylmänkukka, vilukukka.
Antennaria dioica, kissankäppä, kissan käpälä.
Artemisia absinthium, koiruoho. - Lääkkeenä.
A. vulgaris, hepohäntä. - "Sen lehdillä haudotaan saunalauteilla kipeitä paikkoja ruumiissa".
Aquilegia vulgaris, kirppa, akleija.
Brassica napus, lanttu.
Campanula, kellokukka.
Calluna vulgaris, kanerva.
Calendula, enkerlummi.
Caltha palustris, sammakonkukka.
Carum carvi, kumina.
Centaurea cyanus, ruiskukka.
Chenopodium album, saviheinä, savikka.
Chaerophyllum silvestre, koiranputki, putkenkukka.
Chrysanthemum leucanthemum, vuohensilmä.
Cirsium heterophyllum, lääväke.
Convallaria majalis, lehmänkielenkukka.
C. polygonatum, harakanvarvas.
Comarum palustre, vesiapila.
Epilobium angustifolium, horsu, horsma.
Equisetum arvense, äijänparta.
Eriophorum polystachium, luippuheinä, niitynnuppuheinä.
E. vaginatum, miekkaheinä.
Fumaria officinalis, peltorassi.
Galeopsis versicolor, peltopeiponen.
Geranium silvaticum, variksenkukka.
Geum rivale, ruumiinsilmänkukka.
Gymnadenia, käärmeenkiekukukka.
Lathyrus pratensis, keltanätky.
L. vernus, kurjenkukka.
Ledum palustre, suopursu. - Siitä keitettyä lääkettä juodaan keuhkotautiin.
Linnaea borealis, kiimaruoho, jäsenheinä. - Saadaan lääkettä jäsentautiin.
Lychnis viscaria, tervakukka.
Lycopodium, katinlieko.
Majanthemum bifolium, lampaankielenkukka.
Matricaria discoidea, saunamaija - lääkettä vatsatauteihin.
Melampyrum, maitoheinä.
Myosotis, lemmenkukka.
Orchis macutata, Jeesuksen kämmenkukka, myös: käärmeenkiekukukka.
Oxalis acetosella, ketunleipä.
Papaver somniferum, palmu.
Paris quadrifolia, harakanmarja.
Plantago major, rautalehti.
Polypodium vulgäre, kivenimeläinen.
Polystichum ja Pteris, sananjalka.
Potentilla tormentilla, järvänänjuuri. - Juuri hienonnetaan, pannaan viinaan ja juodaan sydäntautia vastaan.
Ranunculus acris ja repens, voikukka.
Raphanus raphanistrum, koirannauris.
Rhamnus frangula, taikinapuu.
Rhinanthus, tasku.
Rosa cinnamomea, orjantappura.
Rubus chamaemorus, muurain.
R. arcticus, maarain.
R. idaeus, vattu.
R. saxatilis, hillikka.
Rumex acetosa ja acetosella, suolakka.
R. domestica, tulikukka.
Sedum acre, maksaruoho.
S. telephium, posliinikukka.
Spiraea ulmaria, ankeriaankukka.
Steltaria media, ves'heinä.
S graminea, täht'heinä.
Syringa vulgaris, syreeni.
Tanacetum vulgäre, nappikukka.
Taraxacum officinale, siansilmä.
Thlaspi arvense, taskuheinä.
Trifolium, apilaankukka.
Trientalis europaea, hirsollinkukka.
Urtica dioica, nokkonen.
U. urens, viholainen.
Vaccinium uliginosum, juovikka.
V. oxycoccus, karpale.
Veronica chamaedrys, metsäminttu.
Viburnum opulus, koiranhöyspuu.
Vicia cracca, hiirennätky, hiirenherne.
Viola canina, äienkukka.
V. tricolor, äienkukka, orvonkukka.
----
b. keräili Sodankylästä kesällä 1909 V. W Westerlund.
Achillea millefolium, Pietarin ruoho. - Pantiin ennen tupakan sekaan.
Aira caespitosa, sääriheinä.
Calluna vulgaris, palokanerva.
Cetraria islandica.lislannin jäkälä. - Ennen keitettiin siitä ja jauhoista liisteriä.
Comarum palustre, kurjenpolvi.
Daphne mezereum, näsenimarja, riisimarja. - Käytetään lääkekasvina sekä sisällisesti että ulkonaisesti. Marjoista tehdään riisivoidetta, jota käytetään syöpää vastaan ihmisessä. Jos riisivoide nostaa ihon, niin sitten on syöpätautiin sairastunut ja lääke sen parantaa. Tällä voidellaan 3:na (alikuun?) tuorstaina ja pannaan tukko päälle. Jos nainen, ennenkuin hän synnyttää, vähitellen ottaa sisällisesti kolme yhdeksää näsenimarjaa, niin lapsi ei voi sairastua syöpätautiin. Jos päätä kolottaa, voidellaan otsa ja korvantaukset ja pannaan tukkopäälle.
Voidetta tehdään näin:
1. kolme yhdeksää marjaa, voita, tulikiveä, tervaa tai männyn pihkaa sekoitetaan.
2. kolme yhdeksää marjaa tehdään pulveriksi, tupakkia purraan ja syljetään siihen.
Equisetum sylvaticum, karvakorte.
E. hiemale, rautakorte. - Poleerataan puuta ja rautaa.
Galeopsis versicolor, nukluvainen.
Hierohloe{?), hajuheinä.
Juncus, sältinki.
Ledum palustre, kanerva. - Kun se kukkii, on kontiolla kiima-aika.
Lycopodium selago, riisiruoho. - Lääkekasvi. Kasvi keitetään maidon kanssa, ja keitto otetaan sisällisesti syöpää ja riisitautia vastaan. Lääke panee ensin huonoksi (oksentamaan), mutta sitten seuraa parantuminen. Terveelle ihmiselle ei lääke vaikuta mitään. Jos se on aijottu miehille, otetaan semmoinen riisiruoho, jossa on kolme haaraa (tähkää), vaimolle tai lapsille kaksihaarainen.
Melampyrum, nipla. - Lehmien herkku.
Menyanthes trifoliata, raake.
Polygonum aviculare, paskaheinä.
Potamogeton natans, koirankielirikka.
Ranunculus repens, voikukka.
Rumex domesticus, suolahorma.
Silene inflata, kukkaro.
Solidago virgaurea, pyynkaali.
Sparganium, limarikka.
Spiraea uimaria, angerva. - Heinänteko alkaa, kun se kukkii.
Veronica longifolia, palo- tai keltahorma.
Viola (palustris?), kilpukka.
20.7.14
Lycaena-perhos-suvun sininen väri ja sukupuolivalinta.
Luonnon ystävä 4, 1909
Harry Federlay.
Darwinin sukupuolivalintaoppi on, kuten tunnettu, herättänyt lukuisia väitteitä eläintieteellisessä maailmassa. Jo Darwinin aikalainen ja ystävä, luonnollisen valinnan innokas puolustaja Wallace ei voinut hyväksyä tätä uutta teoriaa, ja nykyään on useita eläintieteilijöitä, jotka ovat vastustavalla kannalla tämän opin suhteen. Mutta on toiselta puolen tämän opin innokkaita puolustajiakin, joitten joukossa Weismann epäilemättä on mainittava ensimäisenä. Hänen voidaan sanoa olevan enemmän darvinistinen kuin Darwin itse, sillä viimemainittu piti sekä luonnollista että sukupuolivalintaoppiansa ainoastaan kehitysvaikuttimina muiden tunnettujen ja vielä tuntemattomien voimien ohella, jota vastoin Weismann katsoo niitä kaikkivaltiaiksi eikä välitä juuri mitään muista kehitysteorioista.
Kuvaavana esimerkkinä sukupuolivalinnan vaikutuksesta Weismann huomauttaa Lyccena-sukuun kuuluvien perhosten sinistä väriä. Tässä perhossuvussa löytyy näet sekä sinisiä että ruskeita perhosia, ja Weismann arvelee, että ruskea väri on alkuperäinen, ja siitä syystä hän pitää niitä lajeja, joilla molemmat sukupuolet ovat ruskeat, niinkuin esimerkiksi Suomessa esiintyviä lajeja L. eumedon ja L. astrarche, fylogeneettisesti vanhimpina. Tähän alkuperäiseen ruskeaan väriin olisi sitten sukupuolivalinta aikojen kuluessa vaikuttanut sillä lailla, että se uroksilla vähitellen olisi muuttunut siniseksi. Tällä kehitysasteella olisivat nykyään useimmat meidän Lycaena-lajeistamme, sillä niiden urosten väri on sininen, jota vastoin naaraat yleensä ovat ruskeat, vaikka sininen väri niilläkin jo voi näyttäytyä. Niin löytyy esimerkiksi Etelä-Euroopassa eräs laji meleager, jonka naarailla on huomattava väridimorfismi, sillä sekä ruskeita että sinisiä naaraita on olemassa. Myöskin Suomessa tavallisella icarus-lajilla on naaraita, jotka ovat melkein aivan sinisiä ja toisia, joiden väri on puhtaan ruskea; mutta tässä tapauksessa voidaan tavata kaikki välimuodot. Vihdoin olisi sitten sininen väri siirtynyt naaraaseen, niin että molemmat sukupuolet olisivat muuttuneet sinisiksi, niinkuin esimerkiksi arion-lajilla.
Tämä Weismannin selitys tuntuu hyvin luonnolliselta, ja epäilemättä sillä onkin yleinen kannatus. Mutta pari vuotta sitten on kuitenkin etevä virolainen hyönteistutkija W. Petersen julkaissut kirjoituksen, jossa hän osoittaa, että asianlaita ei olekaan sellainen kuin Weismann selittää, vaan aivan päinvastainen. Sininen väri olisi siis alkuperäinen, ruskea sitä vastoin myöhemmin kehittynyt ja ensiksi esiintynyt naarailla vähitellen siirtyen uroksiin. Tämä Weismannin mukaan niin painava todistus sukupuolivalinnan suuresta voimasta lajien kehityksessä, jonka todenperäisyydestä ei voisi olla muuta kuin yksi mielipide, on siis Petersenin tutkimusten kautta muuttunut todistukseksi sukupuolivalinnan täydellisestä voimattomuudesta ainakin tässä tapauksessa.
Seuratkaamme nyt Petersenin tutkimuksia.
Petersen on jo monta vuotta omistanut aikansa perhosten siitinelimien tutkimiseen, ja hän on sitä tehdessään huomannut, että nämät elimet sekä morfologisessa että systemaattisessa suhteessa antavat erittäin hyviä tuntomerkkejä. Tutkiessaan Lycaena-suvun sukupuolielimiä Petersen hämmästyksekseen havaitsi, että tämä elimistö muutamilla lajeilla on hyvin alkuperäinen rakenteeltaan. Useilla uroksilla ovat nimittäin testikset ja niiden tiehyeet vielä parilliset, mitä ei tavata muilla kuin kaikkein alkuperäisimmillä perhosryhmillä kuten esimerkiksi Hepialideilla. Mutta omituista kyllä tämä siitinelimien fylogeneettisessä suhteessa vanhin muoto esiintyy juuri niillä lajeilla, joilla molemmat sukupuolet ovat siniset, esimerkiksi arion-lajilla. Niillä lajeilla taas, joiden naaraat ovat ruskeat ja urokset siniset, kuten icarus y. m., ovat testikset yhtyneet, mutta vielä selvästi voi nähdä niiden olevan parillista syntyperää. Vihdoin on eräillä lajeilla, joiden kumpikin sukupuoli on ruskea, esim. astrarchella, melkein aivan yhtenäinen testis. Petersen on tutkinut kaikkien Euroopassa lentelevien lajien siitinelimiä ja saanut hyvän sarjan lukuisine välimuotoineen, joka selvästi todistaa, että tämä elimistö on kehittynyt rinnakkain värimuutoksen kanssa sinisestä ruskeaan. Siitinelimien kehittymisestä päättäen siis siniset muodot olisivat vanhimmat ja ruskeat nuorimmat. Ne lajit taas, joiden urokset ovat siniset, naarakset sitä vastoin ruskeat, olisivat välimuotoja, joiden naaraat jo olisivat saavuttaneet ruskean värin, jota vastoin urokset vielä pysyisivät vanhalla kehitysasteella. Siis on naaras tässä tapauksessa korkeammin kehittynyt kuin uros, jonka tähden yleisesti levinnvt käsitys urospuolen preponderanssista ei pidä paikkaansa.
Vahvistaaksensa tätä mielipidettänsä Lycaena-lajien fylogeneettisestä iästä on Petersen koettanut hakea todistuksia muistakin elimistä ja vihdoin hänen on onnistunut löytää sellainen siipisuomujen väristä.
Kuten tunnettu, riippuu perhossiiven väri suomuista ja syntyy se kahdella eri tavalla, joko pigmentin avulla, joka täyttää pussimaisen suomun, tahi suomun pinnan rakenteen kautta, joka heijastaa eräät valonsäteet ja siten muodostaa värin. Ensinmainitulla tavalla syntyy ruskea väri, jota vastoin sininen väri melkein kaikkialla, missä se luonnossa ilmestyy, on niin kutsuttu optillinen väri, s. o. se riippuu pinnan rakenteesta. Mutta niin kutsuttu "trübes Medium", jossa pienimmät aineosat ovat niin hienosti jakaantuneet, että ainoastaan ne valonsäteet, joiden aaltopituus on lyhyt, heijastuvat, voi myöskin saada sinisen värin aikaan. On hyvin vaikeaa ratkaista, onko Lycaena-lajien sininen väri puhtaasti optillinen, vai vaikuttaako sen syntymiseen myöskin "trübes Medium", sillä jos Weismannin tavoin käytetään kemiallisia aineita, jotka liuottavat väriaineet, muuttuu suomujen pintarakennekin samalla kertaa. Aivan satunnaisesti Petersenin kuitenkin onnistui päästä tästä kysymyksestä selville. Hän löysi näet yksilön, joka oli täydellinen albinos, sen suomuista puuttuivat väriaineet täydellisesti. Tämä albinosyksilö todisti nyt, että ainoastaan suomujen pinnan rakenne saa aikaan sinisen värin, sillä tämä perhonen oli läpilankeavassa valossa mikroskoopilla tarkastaessa, vaalean keltainen niinkuin normaali Lycaena, mutta jos sitä katseltiin vinosti yläpuolelta heijastetussa valossa tummalla pohjalla, oli se kauniin sininen, jota vastoin alapuoli samoilla edellytyksillä oli aivan valkea. Tämä epänormaali yksilö siis epäilemättä todisti Lycaena-suvun sinisen värin olevan luonteeltansa optillisen.
Näiden tuloksien nojalla, joihin Petersen tutkiessaan yllä mainittua albinistista yksilöä oli tullut, koetti hän nyt saada selkoa kysymyksestä, missä suhteessa optillinen väri on pigmenttiväriin? Koska perhossiiven suomut peittävät toisiansa limittäisesti, riippuu siiven väri tietysti suomujen peittymättömästä kärkiosasta. Sen johdosta Petersen arveli, että jos ruskea pigmenttiväri olisi Lycaenam alkuperäinen väri, niinkuin Weismann väittää, niin suomujen peitetyn tyviosan täytyisi olla ruskea, jota vastoin sininen väri ilmestyisi ensiksi kärkiosaan. Jos taas asianlaita olisi päinvastainen, niinkuin Petersen otaksuu, niin suomujen kärkipuolen pitäisi sisältää ruskeaa pigmenttiä, jota vastoin vanhempaa, sinistä väriä mahdollisesti vielä voisi tavata sen peitetyssä tyviosassa, jossa sitä ei näy, ja josta se siis ei olisi hävinnyt, koska se olemassa olon taistelussa on ilman merkitystä.
Petersenin tutkimukset näyttävät nyt loistavalla tavalla, että hänen mielipiteensä on oikea, ja että Weismann tässä kysymyksessä on aivan väärässä, sillä kummassakin sukupuolessa esiintyy aivan ruskeillakin lajeilla vielä suomun tyviosassa hyvin selvästi omituinen sininen väri, jota vastoin kärkipuoli on aivan himmeän ruskea.
Koska Petersen tutkiessaan kahta aivan erilaista elintä, nimittäin siitinelimiä ja siiven suomuja, on voinut todistaa, että nämät sinisillä lajeilla ovat alkuperäisemmällä kannalla, voimme minusta yhtyä hänen mielipiteeseensä ja katsoa sinisen värin ruskeaa vanhemmaksi ja sen johdosta selittää Weismannin teorian sukupuolivalinnan vaikutuksesta tässä tapauksessa aivan vääräksi.
Yllä käsitelty kysymys muuten osoittaa, kuinka varovainen täytyy olla keksiessä uusia hypoteeseja ja niiden nojalla tehdessä päätöksiä, sillä juuri Lycaena-suvun värisuhteita on kaikissa kehitysopillisissa teoksissa pidetty mitä todistavimpina esimerkkeinä sukupuolivalinnan lajia-muuttelevasta vaikutuksesta, kuten muun muassa voimme nähdä Plåten viime vuonna ilmestyneessä etevässä teoksessa "Darwinsches Selektionsprinzip", jossa Weismannin mielipiteitä Lycaena-suvun värisuhteista laajasti selostetaan, Petersenin tutkimuksista sitä vastoin ei mainita mitään.
Harry Federlay.
Darwinin sukupuolivalintaoppi on, kuten tunnettu, herättänyt lukuisia väitteitä eläintieteellisessä maailmassa. Jo Darwinin aikalainen ja ystävä, luonnollisen valinnan innokas puolustaja Wallace ei voinut hyväksyä tätä uutta teoriaa, ja nykyään on useita eläintieteilijöitä, jotka ovat vastustavalla kannalla tämän opin suhteen. Mutta on toiselta puolen tämän opin innokkaita puolustajiakin, joitten joukossa Weismann epäilemättä on mainittava ensimäisenä. Hänen voidaan sanoa olevan enemmän darvinistinen kuin Darwin itse, sillä viimemainittu piti sekä luonnollista että sukupuolivalintaoppiansa ainoastaan kehitysvaikuttimina muiden tunnettujen ja vielä tuntemattomien voimien ohella, jota vastoin Weismann katsoo niitä kaikkivaltiaiksi eikä välitä juuri mitään muista kehitysteorioista.
Kuvaavana esimerkkinä sukupuolivalinnan vaikutuksesta Weismann huomauttaa Lyccena-sukuun kuuluvien perhosten sinistä väriä. Tässä perhossuvussa löytyy näet sekä sinisiä että ruskeita perhosia, ja Weismann arvelee, että ruskea väri on alkuperäinen, ja siitä syystä hän pitää niitä lajeja, joilla molemmat sukupuolet ovat ruskeat, niinkuin esimerkiksi Suomessa esiintyviä lajeja L. eumedon ja L. astrarche, fylogeneettisesti vanhimpina. Tähän alkuperäiseen ruskeaan väriin olisi sitten sukupuolivalinta aikojen kuluessa vaikuttanut sillä lailla, että se uroksilla vähitellen olisi muuttunut siniseksi. Tällä kehitysasteella olisivat nykyään useimmat meidän Lycaena-lajeistamme, sillä niiden urosten väri on sininen, jota vastoin naaraat yleensä ovat ruskeat, vaikka sininen väri niilläkin jo voi näyttäytyä. Niin löytyy esimerkiksi Etelä-Euroopassa eräs laji meleager, jonka naarailla on huomattava väridimorfismi, sillä sekä ruskeita että sinisiä naaraita on olemassa. Myöskin Suomessa tavallisella icarus-lajilla on naaraita, jotka ovat melkein aivan sinisiä ja toisia, joiden väri on puhtaan ruskea; mutta tässä tapauksessa voidaan tavata kaikki välimuodot. Vihdoin olisi sitten sininen väri siirtynyt naaraaseen, niin että molemmat sukupuolet olisivat muuttuneet sinisiksi, niinkuin esimerkiksi arion-lajilla.
Tämä Weismannin selitys tuntuu hyvin luonnolliselta, ja epäilemättä sillä onkin yleinen kannatus. Mutta pari vuotta sitten on kuitenkin etevä virolainen hyönteistutkija W. Petersen julkaissut kirjoituksen, jossa hän osoittaa, että asianlaita ei olekaan sellainen kuin Weismann selittää, vaan aivan päinvastainen. Sininen väri olisi siis alkuperäinen, ruskea sitä vastoin myöhemmin kehittynyt ja ensiksi esiintynyt naarailla vähitellen siirtyen uroksiin. Tämä Weismannin mukaan niin painava todistus sukupuolivalinnan suuresta voimasta lajien kehityksessä, jonka todenperäisyydestä ei voisi olla muuta kuin yksi mielipide, on siis Petersenin tutkimusten kautta muuttunut todistukseksi sukupuolivalinnan täydellisestä voimattomuudesta ainakin tässä tapauksessa.
Seuratkaamme nyt Petersenin tutkimuksia.
Petersen on jo monta vuotta omistanut aikansa perhosten siitinelimien tutkimiseen, ja hän on sitä tehdessään huomannut, että nämät elimet sekä morfologisessa että systemaattisessa suhteessa antavat erittäin hyviä tuntomerkkejä. Tutkiessaan Lycaena-suvun sukupuolielimiä Petersen hämmästyksekseen havaitsi, että tämä elimistö muutamilla lajeilla on hyvin alkuperäinen rakenteeltaan. Useilla uroksilla ovat nimittäin testikset ja niiden tiehyeet vielä parilliset, mitä ei tavata muilla kuin kaikkein alkuperäisimmillä perhosryhmillä kuten esimerkiksi Hepialideilla. Mutta omituista kyllä tämä siitinelimien fylogeneettisessä suhteessa vanhin muoto esiintyy juuri niillä lajeilla, joilla molemmat sukupuolet ovat siniset, esimerkiksi arion-lajilla. Niillä lajeilla taas, joiden naaraat ovat ruskeat ja urokset siniset, kuten icarus y. m., ovat testikset yhtyneet, mutta vielä selvästi voi nähdä niiden olevan parillista syntyperää. Vihdoin on eräillä lajeilla, joiden kumpikin sukupuoli on ruskea, esim. astrarchella, melkein aivan yhtenäinen testis. Petersen on tutkinut kaikkien Euroopassa lentelevien lajien siitinelimiä ja saanut hyvän sarjan lukuisine välimuotoineen, joka selvästi todistaa, että tämä elimistö on kehittynyt rinnakkain värimuutoksen kanssa sinisestä ruskeaan. Siitinelimien kehittymisestä päättäen siis siniset muodot olisivat vanhimmat ja ruskeat nuorimmat. Ne lajit taas, joiden urokset ovat siniset, naarakset sitä vastoin ruskeat, olisivat välimuotoja, joiden naaraat jo olisivat saavuttaneet ruskean värin, jota vastoin urokset vielä pysyisivät vanhalla kehitysasteella. Siis on naaras tässä tapauksessa korkeammin kehittynyt kuin uros, jonka tähden yleisesti levinnvt käsitys urospuolen preponderanssista ei pidä paikkaansa.
Vahvistaaksensa tätä mielipidettänsä Lycaena-lajien fylogeneettisestä iästä on Petersen koettanut hakea todistuksia muistakin elimistä ja vihdoin hänen on onnistunut löytää sellainen siipisuomujen väristä.
Kuten tunnettu, riippuu perhossiiven väri suomuista ja syntyy se kahdella eri tavalla, joko pigmentin avulla, joka täyttää pussimaisen suomun, tahi suomun pinnan rakenteen kautta, joka heijastaa eräät valonsäteet ja siten muodostaa värin. Ensinmainitulla tavalla syntyy ruskea väri, jota vastoin sininen väri melkein kaikkialla, missä se luonnossa ilmestyy, on niin kutsuttu optillinen väri, s. o. se riippuu pinnan rakenteesta. Mutta niin kutsuttu "trübes Medium", jossa pienimmät aineosat ovat niin hienosti jakaantuneet, että ainoastaan ne valonsäteet, joiden aaltopituus on lyhyt, heijastuvat, voi myöskin saada sinisen värin aikaan. On hyvin vaikeaa ratkaista, onko Lycaena-lajien sininen väri puhtaasti optillinen, vai vaikuttaako sen syntymiseen myöskin "trübes Medium", sillä jos Weismannin tavoin käytetään kemiallisia aineita, jotka liuottavat väriaineet, muuttuu suomujen pintarakennekin samalla kertaa. Aivan satunnaisesti Petersenin kuitenkin onnistui päästä tästä kysymyksestä selville. Hän löysi näet yksilön, joka oli täydellinen albinos, sen suomuista puuttuivat väriaineet täydellisesti. Tämä albinosyksilö todisti nyt, että ainoastaan suomujen pinnan rakenne saa aikaan sinisen värin, sillä tämä perhonen oli läpilankeavassa valossa mikroskoopilla tarkastaessa, vaalean keltainen niinkuin normaali Lycaena, mutta jos sitä katseltiin vinosti yläpuolelta heijastetussa valossa tummalla pohjalla, oli se kauniin sininen, jota vastoin alapuoli samoilla edellytyksillä oli aivan valkea. Tämä epänormaali yksilö siis epäilemättä todisti Lycaena-suvun sinisen värin olevan luonteeltansa optillisen.
Näiden tuloksien nojalla, joihin Petersen tutkiessaan yllä mainittua albinistista yksilöä oli tullut, koetti hän nyt saada selkoa kysymyksestä, missä suhteessa optillinen väri on pigmenttiväriin? Koska perhossiiven suomut peittävät toisiansa limittäisesti, riippuu siiven väri tietysti suomujen peittymättömästä kärkiosasta. Sen johdosta Petersen arveli, että jos ruskea pigmenttiväri olisi Lycaenam alkuperäinen väri, niinkuin Weismann väittää, niin suomujen peitetyn tyviosan täytyisi olla ruskea, jota vastoin sininen väri ilmestyisi ensiksi kärkiosaan. Jos taas asianlaita olisi päinvastainen, niinkuin Petersen otaksuu, niin suomujen kärkipuolen pitäisi sisältää ruskeaa pigmenttiä, jota vastoin vanhempaa, sinistä väriä mahdollisesti vielä voisi tavata sen peitetyssä tyviosassa, jossa sitä ei näy, ja josta se siis ei olisi hävinnyt, koska se olemassa olon taistelussa on ilman merkitystä.
Petersenin tutkimukset näyttävät nyt loistavalla tavalla, että hänen mielipiteensä on oikea, ja että Weismann tässä kysymyksessä on aivan väärässä, sillä kummassakin sukupuolessa esiintyy aivan ruskeillakin lajeilla vielä suomun tyviosassa hyvin selvästi omituinen sininen väri, jota vastoin kärkipuoli on aivan himmeän ruskea.
Koska Petersen tutkiessaan kahta aivan erilaista elintä, nimittäin siitinelimiä ja siiven suomuja, on voinut todistaa, että nämät sinisillä lajeilla ovat alkuperäisemmällä kannalla, voimme minusta yhtyä hänen mielipiteeseensä ja katsoa sinisen värin ruskeaa vanhemmaksi ja sen johdosta selittää Weismannin teorian sukupuolivalinnan vaikutuksesta tässä tapauksessa aivan vääräksi.
Yllä käsitelty kysymys muuten osoittaa, kuinka varovainen täytyy olla keksiessä uusia hypoteeseja ja niiden nojalla tehdessä päätöksiä, sillä juuri Lycaena-suvun värisuhteita on kaikissa kehitysopillisissa teoksissa pidetty mitä todistavimpina esimerkkeinä sukupuolivalinnan lajia-muuttelevasta vaikutuksesta, kuten muun muassa voimme nähdä Plåten viime vuonna ilmestyneessä etevässä teoksessa "Darwinsches Selektionsprinzip", jossa Weismannin mielipiteitä Lycaena-suvun värisuhteista laajasti selostetaan, Petersenin tutkimuksista sitä vastoin ei mainita mitään.
19.7.14
18.7.14
17.7.14
Paints made of Copper. Utilizing Waste - Precautions Against Poisoning.
Manufacturer and builder 9, 1871
When speaking of the so-called Neuwider green, it was mentioned that, by its manufacture, liquids are left which still contain free arsenious acid, acetic acid, and dissolved Schweinflirter green. In case the latter is made from blue vitriol and acetate of soda, after one of the methods described by us, then the liquids left contain sulphate of soda, which is formed by the sulphuric acid of the blue vitriol combining with the soda, while its acetic acid combines with the copper oxide of the blue vitriol to verdigris or acetate of copper. The sulphate of soda remains then passive in the liquid, and the paint combines with only a portion of the acetic and arsenious acids. These remaining liquids being a diluted arsenious vinegar, are therefore easily utilized in the manufacture of successive greens.
A remnant solution from 100 pounds verdigris may be considered as still containing two thirds of the vinegar, besides some 20 pounds of arsenious acid, and the remnant solution of acetate of soda made from 165 pounds sulphate of soda, and 40 pounds of acetic acid or acetate of soda, and used for the manufacture of Schweinfiirter green, contains one third, or 20 pounds, of the acetic acid, and also 20 pounds of arsenious acid, both solutions being consequently very poisonous.
All these arsenious copper paints require great care in manufacture, on account of the arsenic used; and this is especially the case with the Neuwider and other greens, in which large quantities of this substance are manufactured. This arsenious acid may be obtained in the trade, either in lumps or in powder; in the former state, it is more sure to be free of adulteration, and therefore preferred by some. It is prepared for use by pulverization in large iron mortars. In order to protect the workman from the fatally poisonous dust, it should be pulverized under water, and afterward ground in a mill, the same precaution being observed.
Personal Precautions
Every workman in this branch of business should keep himself scrupulously clean. Neither the dust of the arsenic nor of the green paint should be allowed to remain on his clothes. It has a tendency to adhere to the skin of the hands, and especially to stick below and around the nails; therefore the hands must not touch any more sensitive part of the body before scrupulous cleaning. They should not be kept longer in the arsenious solutions than is absolutely necessary, as otherwise the laborer is soon attacked by the ar-senic disease. Unfortunately, the contact with the liquids, and the dust in sifting and packing, can not be totally avoided. The influence of the vapors developed by the boiling arsenious solutions is greatly removed by placing the boilers in well-ventilated buildings, with proper arrangements to cause the fones to ascend rapidly out of harm's way; but in spite of every precaution, in the course of time the laborers are bound to suffer.
Arsenic Disease.
Thins far no remedy has been discovered to prevent the final attack of the peculiar disease caused by the external exposure of the body to arsenic. It commences with a burning sensation between the thighs, the lower abdomen, and genitals. Suppurating ulcers appear there, and afterward the same symptoms show themselves around the nostrils. As soon as this is the case, the laborer must be removed from work, when in three to four weeks the sores will heal without leaving any injurious results whatsoever; the healing power of nature drives out the injurious substances by suppuration, and therefore should not be interfered with, but as much as possible promoted. As soon as the cause of the ulcers is removed, they heal by themselves, and most not be interfered with by plasters or so-called healing salves.
In case the laborers are not at once removed from the works as soon as the symptoms described show themselves, they soon grow worse, so much so that in two or three weeks they are unable to walk, when it will take several months to insure their recovery, which often becomes doubtful, especially when their systems are undermined with the habitual use of tobacco or strong drink.
For this reason, in all well-regulated factories the laborers are periodically removed from this branch of the business, as soon as the first symptom shows itself, and then no further inconvenience is experienced. After four or five weeks, they may resume the same kind of labor.
The copper paints are likewise very poisonous, especially these containing the most arsenic. There are scores of instances where injurious effects resulted, not only froth. such paints entering the stomach, but from external contact. We will only mention one of our own experiences. Many years ago, we wore in the chemical laboratory a cap similar to the so-called smoking-caps; it was internally lined with a strip of green leather, which touched hair and forehead. In a short time some very sore suppurating pimples showed themselves; the cap was suspected and abandoned, when they healed in a short time. In order to experiment, the cap was again used, when the same symptoms showed themselves. It was thus considered sure that the cap was the cause. A piece of the leather being chemically tested, showed the presence of arsenic, proving that it had been colored with one of the pigments described, (the arseniate of copper kind.)
All these arseniate of copper greens are used as oil and water-colors; it is, however, somewhat difficult to rub them very fine, and as oil-colors they are deficient in body and do not cover very well; in this respect they are inferior to the different kinds of chrome greens. However, they have the advantage over the latter of withstanding in a greater degree the influence of air and light; on fresh lime they can not be used, as the caustic lime withdraws the acetic acid, and a yellowish green arseniate of copper remains which has a disagreeable color. Sulphurous vapors also act injuriously, as they change the green to a brown tint.
With this paper our series of articles on the paints made of copper is concluded.
When speaking of the so-called Neuwider green, it was mentioned that, by its manufacture, liquids are left which still contain free arsenious acid, acetic acid, and dissolved Schweinflirter green. In case the latter is made from blue vitriol and acetate of soda, after one of the methods described by us, then the liquids left contain sulphate of soda, which is formed by the sulphuric acid of the blue vitriol combining with the soda, while its acetic acid combines with the copper oxide of the blue vitriol to verdigris or acetate of copper. The sulphate of soda remains then passive in the liquid, and the paint combines with only a portion of the acetic and arsenious acids. These remaining liquids being a diluted arsenious vinegar, are therefore easily utilized in the manufacture of successive greens.
A remnant solution from 100 pounds verdigris may be considered as still containing two thirds of the vinegar, besides some 20 pounds of arsenious acid, and the remnant solution of acetate of soda made from 165 pounds sulphate of soda, and 40 pounds of acetic acid or acetate of soda, and used for the manufacture of Schweinfiirter green, contains one third, or 20 pounds, of the acetic acid, and also 20 pounds of arsenious acid, both solutions being consequently very poisonous.
All these arsenious copper paints require great care in manufacture, on account of the arsenic used; and this is especially the case with the Neuwider and other greens, in which large quantities of this substance are manufactured. This arsenious acid may be obtained in the trade, either in lumps or in powder; in the former state, it is more sure to be free of adulteration, and therefore preferred by some. It is prepared for use by pulverization in large iron mortars. In order to protect the workman from the fatally poisonous dust, it should be pulverized under water, and afterward ground in a mill, the same precaution being observed.
Personal Precautions
Every workman in this branch of business should keep himself scrupulously clean. Neither the dust of the arsenic nor of the green paint should be allowed to remain on his clothes. It has a tendency to adhere to the skin of the hands, and especially to stick below and around the nails; therefore the hands must not touch any more sensitive part of the body before scrupulous cleaning. They should not be kept longer in the arsenious solutions than is absolutely necessary, as otherwise the laborer is soon attacked by the ar-senic disease. Unfortunately, the contact with the liquids, and the dust in sifting and packing, can not be totally avoided. The influence of the vapors developed by the boiling arsenious solutions is greatly removed by placing the boilers in well-ventilated buildings, with proper arrangements to cause the fones to ascend rapidly out of harm's way; but in spite of every precaution, in the course of time the laborers are bound to suffer.
Arsenic Disease.
Thins far no remedy has been discovered to prevent the final attack of the peculiar disease caused by the external exposure of the body to arsenic. It commences with a burning sensation between the thighs, the lower abdomen, and genitals. Suppurating ulcers appear there, and afterward the same symptoms show themselves around the nostrils. As soon as this is the case, the laborer must be removed from work, when in three to four weeks the sores will heal without leaving any injurious results whatsoever; the healing power of nature drives out the injurious substances by suppuration, and therefore should not be interfered with, but as much as possible promoted. As soon as the cause of the ulcers is removed, they heal by themselves, and most not be interfered with by plasters or so-called healing salves.
In case the laborers are not at once removed from the works as soon as the symptoms described show themselves, they soon grow worse, so much so that in two or three weeks they are unable to walk, when it will take several months to insure their recovery, which often becomes doubtful, especially when their systems are undermined with the habitual use of tobacco or strong drink.
For this reason, in all well-regulated factories the laborers are periodically removed from this branch of the business, as soon as the first symptom shows itself, and then no further inconvenience is experienced. After four or five weeks, they may resume the same kind of labor.
The copper paints are likewise very poisonous, especially these containing the most arsenic. There are scores of instances where injurious effects resulted, not only froth. such paints entering the stomach, but from external contact. We will only mention one of our own experiences. Many years ago, we wore in the chemical laboratory a cap similar to the so-called smoking-caps; it was internally lined with a strip of green leather, which touched hair and forehead. In a short time some very sore suppurating pimples showed themselves; the cap was suspected and abandoned, when they healed in a short time. In order to experiment, the cap was again used, when the same symptoms showed themselves. It was thus considered sure that the cap was the cause. A piece of the leather being chemically tested, showed the presence of arsenic, proving that it had been colored with one of the pigments described, (the arseniate of copper kind.)
All these arseniate of copper greens are used as oil and water-colors; it is, however, somewhat difficult to rub them very fine, and as oil-colors they are deficient in body and do not cover very well; in this respect they are inferior to the different kinds of chrome greens. However, they have the advantage over the latter of withstanding in a greater degree the influence of air and light; on fresh lime they can not be used, as the caustic lime withdraws the acetic acid, and a yellowish green arseniate of copper remains which has a disagreeable color. Sulphurous vapors also act injuriously, as they change the green to a brown tint.
With this paper our series of articles on the paints made of copper is concluded.
16.7.14
Paints made of Copper. Some Practical Hints in Regard to the Economy and Details in Their Manufacture.
Manufacturer and builder 8, 1871
In some localities it is more economical to use the common sodic sulphate (Glauber's-salt) in place of the soda itself. In this case, the vinegar used, whether it be strong or weak, is first changed into calcic acetate, (acetate of lime,) by adding to a quantity containing 60 pounds of the hydrated acetic acid, dry hydrated lime until it ceases to redden litmus paper. About 42 pounds of lime .will suffice for this; but an excess of lime is to be guarded against. Then a concentrated solution of 165 pounds sodic sulphate is added. The great economy of this process lies in the fact that it may be impure, and even contain some iron. We have the same precipitate of calcic sulphate (sulphate of lime, gypsum, plaster of Paris) as described page 127. and this is to be separated by decantation or filtration, The liquid contains then the acetate of soda, and must be brought to the quantity of about 70 gallons by evaporation of the vinegar used, if the same be weak, or by the addition of water, if it be strong, because the amount of liquid thus obtained will be large or small in proportion as the vinegar used is weak or strong. We have now the solution of sodic acetate, with which we may proceed 'as before described. Circumstances must decide the economy of this process, which may be easily determined by making up an account of the expenses of Glauber's-salt, lime, fuel in evaporation, labor, etc., compared with the cost of the sodic calcic acetate when bought.
One point must not be forgotten, which is, if we dissolve the pure sodic acetate, we have the same in solution. and nothing else; while, when we follow the process here described, we have in the solution not only gypsum, which is soluble in 400 parts water, but also undecomposed calcic acetate, and even free sodic sulphate, because the mutual decomposition is never a complete one, as small quantities of the substances used remain together in solution in their original state. (This is a practical hint to young chemists who labor under the impression that the theory laid down in the elementary text-book is complete, when teaching the mode of mutual decompositions and recompositions.) When, now, a solution of cupric sulphate (blue vitriol) is added to such a mixed solution, we obtain, besides the substances mentioned, some more calcie sulphate, (gypsum and on adding the arsenic solution, a white precipitate will mix with the green, increasing the quantity obtained, but decreasing the quality. This, of course, is not the case when using the pare sodic acetate, or vinegar and soda, from which the brightest greens are always obtained. The practical question is, now, What method pays best under the circumstances, to make smaller quantities of a brighter color, at greater expense, for which a higher price may be obtained, or to make larger quantities of an inferior quality, at less expense, for which a lower price must be charged ?
An important point is, that the colors are brighter and of finer grain when they are formed rapidly in the kettles, and not slowly crystallized.
These colors are assorted by manufacturers, with reference to their light or dark shades, and from the above it is clear why the latter are somewhat higher in price.
This difference in price is increased by adulteration, by the intermixture of gypstim and barytic sulphate, (heavy spar,) producing light shades, as this adulteration of a valuable paint with a comparatively worthless ingredient diminishes its real value in direct proportion to the amount of adulteration, which, However, may be easily detected by the following means:
To 100 grains of the paint, add liquid ammonia; when pure, and if enough ammonia be used, all will dissolve; bat what does not, is adulteration. Place the resonant on a small filter, wash it with water, and dry it; its weight will give the amount of adulteration, and consequently the quantity of pure material. (The filter should be weighed both before use and afterward with the precipitate, and its tare subtracted, a method always followed in similar manipulations.)
It has been found that the color sometimes turns out yellowish-green, when the verdigris used contains very little acetic acid, or when by accident the arsenic is not all dissolved. The Cassel green is a color of this kind. In general there is no great demand for these shades; they are nevertheless manufactured, but not in the manner stated, as the result is exceedingly uncertain; they are simply made by adding chrome-yellow, of the sulphur-yellow or lemon-yellow shade, the method of manufacture of which is described on page 52 of our first volume. In this way the tone of colof may be regulated to any extent.
For the benefit of painters we must here remark, that if the paint is unadulterated, they lose by paying a higher price for the dark, coarse-grained or crystallized qualities, because both, when rubbed up fine, are absolutely equal, the darker appearance being only caused by the coarse grains, which require considerable snore labor to bring to the right condition for use. The body of the paint and its covering qualities are the same.
In this country the chrome-greens have among the house-painters almost entirely superseded the copper compound. The largest consumers are now the dyers, calico-printers, carpet manufacturers, etc., who use it in large quantities for the production of most of the beautiful greens.
The case with these manufacturers is totally different from what it is with painters; as they do not rub up the copper compounds, but use solutions, and only being certain of obtaining the pure material when buying the dark, large-grained crystallized qualities, they do best by paying the higher price, in order to be sure of producing the snore beautiful colors, which in dyeing . can only be obtained by the use of the purest attainable materials.
In some localities it is more economical to use the common sodic sulphate (Glauber's-salt) in place of the soda itself. In this case, the vinegar used, whether it be strong or weak, is first changed into calcic acetate, (acetate of lime,) by adding to a quantity containing 60 pounds of the hydrated acetic acid, dry hydrated lime until it ceases to redden litmus paper. About 42 pounds of lime .will suffice for this; but an excess of lime is to be guarded against. Then a concentrated solution of 165 pounds sodic sulphate is added. The great economy of this process lies in the fact that it may be impure, and even contain some iron. We have the same precipitate of calcic sulphate (sulphate of lime, gypsum, plaster of Paris) as described page 127. and this is to be separated by decantation or filtration, The liquid contains then the acetate of soda, and must be brought to the quantity of about 70 gallons by evaporation of the vinegar used, if the same be weak, or by the addition of water, if it be strong, because the amount of liquid thus obtained will be large or small in proportion as the vinegar used is weak or strong. We have now the solution of sodic acetate, with which we may proceed 'as before described. Circumstances must decide the economy of this process, which may be easily determined by making up an account of the expenses of Glauber's-salt, lime, fuel in evaporation, labor, etc., compared with the cost of the sodic calcic acetate when bought.
One point must not be forgotten, which is, if we dissolve the pure sodic acetate, we have the same in solution. and nothing else; while, when we follow the process here described, we have in the solution not only gypsum, which is soluble in 400 parts water, but also undecomposed calcic acetate, and even free sodic sulphate, because the mutual decomposition is never a complete one, as small quantities of the substances used remain together in solution in their original state. (This is a practical hint to young chemists who labor under the impression that the theory laid down in the elementary text-book is complete, when teaching the mode of mutual decompositions and recompositions.) When, now, a solution of cupric sulphate (blue vitriol) is added to such a mixed solution, we obtain, besides the substances mentioned, some more calcie sulphate, (gypsum and on adding the arsenic solution, a white precipitate will mix with the green, increasing the quantity obtained, but decreasing the quality. This, of course, is not the case when using the pare sodic acetate, or vinegar and soda, from which the brightest greens are always obtained. The practical question is, now, What method pays best under the circumstances, to make smaller quantities of a brighter color, at greater expense, for which a higher price may be obtained, or to make larger quantities of an inferior quality, at less expense, for which a lower price must be charged ?
An important point is, that the colors are brighter and of finer grain when they are formed rapidly in the kettles, and not slowly crystallized.
These colors are assorted by manufacturers, with reference to their light or dark shades, and from the above it is clear why the latter are somewhat higher in price.
This difference in price is increased by adulteration, by the intermixture of gypstim and barytic sulphate, (heavy spar,) producing light shades, as this adulteration of a valuable paint with a comparatively worthless ingredient diminishes its real value in direct proportion to the amount of adulteration, which, However, may be easily detected by the following means:
To 100 grains of the paint, add liquid ammonia; when pure, and if enough ammonia be used, all will dissolve; bat what does not, is adulteration. Place the resonant on a small filter, wash it with water, and dry it; its weight will give the amount of adulteration, and consequently the quantity of pure material. (The filter should be weighed both before use and afterward with the precipitate, and its tare subtracted, a method always followed in similar manipulations.)
It has been found that the color sometimes turns out yellowish-green, when the verdigris used contains very little acetic acid, or when by accident the arsenic is not all dissolved. The Cassel green is a color of this kind. In general there is no great demand for these shades; they are nevertheless manufactured, but not in the manner stated, as the result is exceedingly uncertain; they are simply made by adding chrome-yellow, of the sulphur-yellow or lemon-yellow shade, the method of manufacture of which is described on page 52 of our first volume. In this way the tone of colof may be regulated to any extent.
For the benefit of painters we must here remark, that if the paint is unadulterated, they lose by paying a higher price for the dark, coarse-grained or crystallized qualities, because both, when rubbed up fine, are absolutely equal, the darker appearance being only caused by the coarse grains, which require considerable snore labor to bring to the right condition for use. The body of the paint and its covering qualities are the same.
In this country the chrome-greens have among the house-painters almost entirely superseded the copper compound. The largest consumers are now the dyers, calico-printers, carpet manufacturers, etc., who use it in large quantities for the production of most of the beautiful greens.
The case with these manufacturers is totally different from what it is with painters; as they do not rub up the copper compounds, but use solutions, and only being certain of obtaining the pure material when buying the dark, large-grained crystallized qualities, they do best by paying the higher price, in order to be sure of producing the snore beautiful colors, which in dyeing . can only be obtained by the use of the purest attainable materials.
15.7.14
Paints Made of Copper. Manufacture of Paris or Emerald Green from Blue Vitriol.
Manufacturer and builder 6, 1871
In certain localities, a blue vitriol free from iron, and also vinegar, acetate of lime, or acetate of soda, may be obtained at such a low figure that it is much more economical to manufacture green colors from these ingredients than front verdigris. The details of the operation are as follows
1. With acetate of soda.
In place of 100 lbs. dis-tilled verdigris, take a solution of 136 lbs. crystallized acetate of soda, and 125 lbs. pure blue vitriol, free from iron. The mutual decomposition produces 100 parts of acetate of copper and 161 parts of sulphate of soda, which latter does not interfere in the least with the formation of the color. The remainder of the operation is the same as that explained for the Schweinfurter green, (page 98.)
2. With acetate of lime.
This acetate must be the pure, dry acetate, and not the dirty compound obtained by the distillation of wood. If dry, 80 pounds, and more when moist, are dissolved in about 150 pounds of water. Then 125 pounds of blue vitriol are dis-solved in about 500 pounds of water, and boiled. The solutions are allowed to cool a little, and the former is then poured slowly into the latter, as long as precipitate takes place. All, or nearly all, the acetate is required; what remains is used for the next operation. The precipitate (sulphate of lime) is separated by filtration, while the liquid, containing the acetate of copper (verdigris) in solution, is placed in the copper boiler. The precipitate is washed repeatedly, in order not to lose the adherent verdigris, and the wash-water is used for future solutions, in place of water. However, there always remains, adhering to the precipitate, some basic, less soluble acetate of copper, which can not well be washed out. It is usually preferred, therefore, to change the acetate of lime first into acetate of soda, by mixing the solution of about 80 pounds of acetate of lime, already descrioioed, with one of 165 pounds of crystallized sulphate of sea, (Glauber salts,) as long as a precipitate is formed. This precipitate is an almost pure sulphate of lime, while the acetate of soda remains in a clear solutions. Filtration separates this from the deposit. For the given quantities no more water sheuld be used than GOO pounds altogether. The solution is then placed in the boiler; 125 pounds of blue vitriol are aded, and the further treatment is the same as for a verdi-gris solution.
3. With vinegar.
The vinegar, or acetic acid, must be pure or distilled; but the required quantity depends entirely on its strength. The method of ascertaining this is given in another article. As an equivalent to the use of 100 pounds distilled verdigris, or 100 pounds of arsenic, 60 pounds of hydrated acetic acid is required. If this quantity is mixed with nine times its weight of water, so as to form 600 pounds of vinegar, (or, iu other words, if we have vinegar which contains 10 per cent of acetic acid,) it is only necessary to put the vinegar in the boiler and add 144 pounds of crystallized carbonate of soda, or add the soda until little or no more effervescence takes place. The solution is then acetate of soda, to which 125 pounds of blue vitriol is added, when the solution is acetate of copper, and may be further treated as such. If the same amount of acetic acid is contained in more vinegar, a larger quantity will be needed to be saturated by 144 pounds of carbonate of soda. It may be brought to about 600 pounds by evaporation. To avoid the latter necessity, however, the amount of the weak vinegar is previously determined which will contain 40 pounds of acetic acid. Suppose it is 900 pounds. Of this, 600 pounds is placed in the verdi-gris boiler, and the balance in the arsenic boiler. If necessary, water is added, to obtain the right quantity of liquid in the latter. It is then boiled, and, gradually, 144 pounds of crystallized carbonate of soda are added, until effervescence stops. In the vinegar contained in the verdigris boiler, 125 pounds of blue vitriol is in the mean time dissolved, and when both solutions are ready, that is, when nothing is left undissolved, they are poured together. The vinegar may also be placed in the arsenic boiler, and as soon as all the arsenic is dissolved in the soda solution, (which goes on more rapidly than without soda,) the blue vitriol may be thrown in, dissolved, and drawn off; or the green may be allowed to form in the boiler itself.
All these variations are permitted, and give different greens, as well in regard to size of grains as to shade. The method of using only two thirds as much acetic acid as is present in 100 parts of crystallized verdigris is, in most cases, mere economical than the method of changing all the vinegar first into acetate of lime, and using sulphate of soda in place of the car-bonate, in order to obtain acetate of soda. The shades of green obtained without the use of lime compounds are also clearer and purer, and no sulphate of lime or plaster has a chance to mix with the paint. The same method may also be followed with strong vinegar, taking only two thirds of the otherwise required 60 pounds of hydrated acetic acid in the mass of vinegar, putting the vinegar and the blue vitriol together, boiling the arsenic with the carbonate of soda, and then proceeding as described.
In certain localities, a blue vitriol free from iron, and also vinegar, acetate of lime, or acetate of soda, may be obtained at such a low figure that it is much more economical to manufacture green colors from these ingredients than front verdigris. The details of the operation are as follows
1. With acetate of soda.
In place of 100 lbs. dis-tilled verdigris, take a solution of 136 lbs. crystallized acetate of soda, and 125 lbs. pure blue vitriol, free from iron. The mutual decomposition produces 100 parts of acetate of copper and 161 parts of sulphate of soda, which latter does not interfere in the least with the formation of the color. The remainder of the operation is the same as that explained for the Schweinfurter green, (page 98.)
2. With acetate of lime.
This acetate must be the pure, dry acetate, and not the dirty compound obtained by the distillation of wood. If dry, 80 pounds, and more when moist, are dissolved in about 150 pounds of water. Then 125 pounds of blue vitriol are dis-solved in about 500 pounds of water, and boiled. The solutions are allowed to cool a little, and the former is then poured slowly into the latter, as long as precipitate takes place. All, or nearly all, the acetate is required; what remains is used for the next operation. The precipitate (sulphate of lime) is separated by filtration, while the liquid, containing the acetate of copper (verdigris) in solution, is placed in the copper boiler. The precipitate is washed repeatedly, in order not to lose the adherent verdigris, and the wash-water is used for future solutions, in place of water. However, there always remains, adhering to the precipitate, some basic, less soluble acetate of copper, which can not well be washed out. It is usually preferred, therefore, to change the acetate of lime first into acetate of soda, by mixing the solution of about 80 pounds of acetate of lime, already descrioioed, with one of 165 pounds of crystallized sulphate of sea, (Glauber salts,) as long as a precipitate is formed. This precipitate is an almost pure sulphate of lime, while the acetate of soda remains in a clear solutions. Filtration separates this from the deposit. For the given quantities no more water sheuld be used than GOO pounds altogether. The solution is then placed in the boiler; 125 pounds of blue vitriol are aded, and the further treatment is the same as for a verdi-gris solution.
3. With vinegar.
The vinegar, or acetic acid, must be pure or distilled; but the required quantity depends entirely on its strength. The method of ascertaining this is given in another article. As an equivalent to the use of 100 pounds distilled verdigris, or 100 pounds of arsenic, 60 pounds of hydrated acetic acid is required. If this quantity is mixed with nine times its weight of water, so as to form 600 pounds of vinegar, (or, iu other words, if we have vinegar which contains 10 per cent of acetic acid,) it is only necessary to put the vinegar in the boiler and add 144 pounds of crystallized carbonate of soda, or add the soda until little or no more effervescence takes place. The solution is then acetate of soda, to which 125 pounds of blue vitriol is added, when the solution is acetate of copper, and may be further treated as such. If the same amount of acetic acid is contained in more vinegar, a larger quantity will be needed to be saturated by 144 pounds of carbonate of soda. It may be brought to about 600 pounds by evaporation. To avoid the latter necessity, however, the amount of the weak vinegar is previously determined which will contain 40 pounds of acetic acid. Suppose it is 900 pounds. Of this, 600 pounds is placed in the verdi-gris boiler, and the balance in the arsenic boiler. If necessary, water is added, to obtain the right quantity of liquid in the latter. It is then boiled, and, gradually, 144 pounds of crystallized carbonate of soda are added, until effervescence stops. In the vinegar contained in the verdigris boiler, 125 pounds of blue vitriol is in the mean time dissolved, and when both solutions are ready, that is, when nothing is left undissolved, they are poured together. The vinegar may also be placed in the arsenic boiler, and as soon as all the arsenic is dissolved in the soda solution, (which goes on more rapidly than without soda,) the blue vitriol may be thrown in, dissolved, and drawn off; or the green may be allowed to form in the boiler itself.
All these variations are permitted, and give different greens, as well in regard to size of grains as to shade. The method of using only two thirds as much acetic acid as is present in 100 parts of crystallized verdigris is, in most cases, mere economical than the method of changing all the vinegar first into acetate of lime, and using sulphate of soda in place of the car-bonate, in order to obtain acetate of soda. The shades of green obtained without the use of lime compounds are also clearer and purer, and no sulphate of lime or plaster has a chance to mix with the paint. The same method may also be followed with strong vinegar, taking only two thirds of the otherwise required 60 pounds of hydrated acetic acid in the mass of vinegar, putting the vinegar and the blue vitriol together, boiling the arsenic with the carbonate of soda, and then proceeding as described.
14.7.14
Paints Made of Copper. Schweinfurter green.
Manufacturer and builder 5, 1871
The pure Schweinfurter green consists of 32 parts of oxide of copper, 60 parts of arsenious acid, and 10 of acetic acid. As before mentioned, (see page. 63,) confusion exists in the names given in different localities to this class of paints, and the manner of manufacture we are now going to describe applies to the original Schweinfurter method.
Two large kettles are placed in such a way over the brick furnaces that the contents of both may be drawn off. into a lower receiver. The largest kettle serves for time solution of the arsenic, and most, in case 70 pounds verdigris are to be manipulated at once, be able to contain at least 200 gallons of water with 100 lbs. of arsenic; while the other kettle need only to contain 60 gallons of water to 100 pounds of verdigris. The lower vessel must be large enough to receive time contents of both kettles and admit of time mixing. Time best size is about 300 gallons. Time work is commenced in time evening by placing in time smallest kettle 70 pounds of crushed verdigris with 60 gallons of water. Time next morning time large kettle is filled with 200 gallons of water, (a gauging mark is made in time kettle, to indicate time exact quantity,) and 100 pounds finely-pulverized arsenic is added; fire is then made under this, and afterward under time smaller kettle. Time contents of the larger are brought to the boiling-point, and the boiling contin-ued for five to six hours, or until all time arsenic is dissolved. When this is nearly reached, time evaporated water is replaced by fresh water, so as to retain time ori-ginal bulk, 200 gallons. Time verdigris is then heated to a temperature of about 185° Fahrenheit, but not higher. Of course, time contents must be stirred often, in order to promote time solution of time solids in the water. When time arsenic solution is ready, and kept boiling for half an hour after time supply of time evaporated water, a large copper sieve is placed under the cock of the verdigris kettle, and both cocks are opened full at once. Time solutions are mixed by continuous stirring; but one third of time arsenic solution is kept in time kettle, and only added after time mixture has rested quietly for two or three hours, when time wimole is stirred up again.
It is better to allow the two solutions to settle before mixing, in order that small, solid particles of arsenic may not be carried into the mixture; therefore time fires must be nearly extinguished for about fifteen minutes, so as to stop all motion in time liquids; time verdigris solution is, however, never clear, but resembles a thin paste, and time first precipitate formed in time mixture always has a dirty yellowish-green color. On time top, bubbles show themselves of time bright green color of time paint desired; but time wimole is in a continuous interior agitation, wherefore most of the precipitate remains suspended. Two to three hours, and often sooner, after time remnant of time arsenic solution has been added, time precipitate contracts, and time more it does this, time more beautiful time color will be. At last it forms a crust, adhering firmly to time bottom, and over time same is a blue-green liquid. On top of which a skin of time green paint also floats. The precipitate is crystalline, and its lustre and intensity of color depends on time size and granulation of the crystals; the larger they are, time darker and more intense will be the color. After twenty-four to thirty-six hours, the liquid is drawn off, the paint passed through the proper hair-sieves, drained on linen filters, then dried, pulverized, (which latter is very easy,) and once more sifted in closed boxes, so as not to expose the workmen to the highly poisonous dust.
From 70 pounds verdigris are, in this way, obtained 70 to 80 pounds of Schweinfurter green of the most superior quality. The verdigris here mentioned is of the common kind, which, packed in leathern bags, is an article of extensive commerce in France. It is a basic salt, and contains, besides cupric acetate, also a basic salt, insoluble in water. It produces, therefore, more paint than the pure cupric acetate or the so-called distilled verdigris. (See page 16.) If the latter is used, it is necessary to take 100 pounds in place of 70, in order to obtain 70 or 80 pounds paint; but then the result is better, the crystals are much larger and purer, as the impurities of the common verdigris are absent. The Schweinfurter green obtained in this manner is usually called distilled Schweinfurter green; but frequently the common paint is sold under this name, when accidentally the color turns out a. little better than usual. If made from the distilled verdigris, it need not be passed through a sieve, either wet or dry, because there are no impurities to be removed.
The above is not the simplest manner of operating. However, it is the best, as by the slowness of the process the crystallization goes on without disturbance, which always interferes with perfect crystallization.
If the latter is not considered essential, one may perform the operation by dissolving the arsenic in the large kettle in the proportions given above, and then adding the verdigris paste; and either draw off at once, when the yellowish-green precipitate takes the right color already during the pouring, or it may first be boiled for a short time, when all time color is formed in time kettle, from which it is afterward drawn, or the verdigris may be pulverized, passed through a sieve and mixed in the arsenic solution, or the boiling solution may be poured into time powdered verdigris. Every variation of time methodus operandi will give as result a different shade in the green paint obtained.
The pure Schweinfurter green consists of 32 parts of oxide of copper, 60 parts of arsenious acid, and 10 of acetic acid. As before mentioned, (see page. 63,) confusion exists in the names given in different localities to this class of paints, and the manner of manufacture we are now going to describe applies to the original Schweinfurter method.
Two large kettles are placed in such a way over the brick furnaces that the contents of both may be drawn off. into a lower receiver. The largest kettle serves for time solution of the arsenic, and most, in case 70 pounds verdigris are to be manipulated at once, be able to contain at least 200 gallons of water with 100 lbs. of arsenic; while the other kettle need only to contain 60 gallons of water to 100 pounds of verdigris. The lower vessel must be large enough to receive time contents of both kettles and admit of time mixing. Time best size is about 300 gallons. Time work is commenced in time evening by placing in time smallest kettle 70 pounds of crushed verdigris with 60 gallons of water. Time next morning time large kettle is filled with 200 gallons of water, (a gauging mark is made in time kettle, to indicate time exact quantity,) and 100 pounds finely-pulverized arsenic is added; fire is then made under this, and afterward under time smaller kettle. Time contents of the larger are brought to the boiling-point, and the boiling contin-ued for five to six hours, or until all time arsenic is dissolved. When this is nearly reached, time evaporated water is replaced by fresh water, so as to retain time ori-ginal bulk, 200 gallons. Time verdigris is then heated to a temperature of about 185° Fahrenheit, but not higher. Of course, time contents must be stirred often, in order to promote time solution of time solids in the water. When time arsenic solution is ready, and kept boiling for half an hour after time supply of time evaporated water, a large copper sieve is placed under the cock of the verdigris kettle, and both cocks are opened full at once. Time solutions are mixed by continuous stirring; but one third of time arsenic solution is kept in time kettle, and only added after time mixture has rested quietly for two or three hours, when time wimole is stirred up again.
It is better to allow the two solutions to settle before mixing, in order that small, solid particles of arsenic may not be carried into the mixture; therefore time fires must be nearly extinguished for about fifteen minutes, so as to stop all motion in time liquids; time verdigris solution is, however, never clear, but resembles a thin paste, and time first precipitate formed in time mixture always has a dirty yellowish-green color. On time top, bubbles show themselves of time bright green color of time paint desired; but time wimole is in a continuous interior agitation, wherefore most of the precipitate remains suspended. Two to three hours, and often sooner, after time remnant of time arsenic solution has been added, time precipitate contracts, and time more it does this, time more beautiful time color will be. At last it forms a crust, adhering firmly to time bottom, and over time same is a blue-green liquid. On top of which a skin of time green paint also floats. The precipitate is crystalline, and its lustre and intensity of color depends on time size and granulation of the crystals; the larger they are, time darker and more intense will be the color. After twenty-four to thirty-six hours, the liquid is drawn off, the paint passed through the proper hair-sieves, drained on linen filters, then dried, pulverized, (which latter is very easy,) and once more sifted in closed boxes, so as not to expose the workmen to the highly poisonous dust.
From 70 pounds verdigris are, in this way, obtained 70 to 80 pounds of Schweinfurter green of the most superior quality. The verdigris here mentioned is of the common kind, which, packed in leathern bags, is an article of extensive commerce in France. It is a basic salt, and contains, besides cupric acetate, also a basic salt, insoluble in water. It produces, therefore, more paint than the pure cupric acetate or the so-called distilled verdigris. (See page 16.) If the latter is used, it is necessary to take 100 pounds in place of 70, in order to obtain 70 or 80 pounds paint; but then the result is better, the crystals are much larger and purer, as the impurities of the common verdigris are absent. The Schweinfurter green obtained in this manner is usually called distilled Schweinfurter green; but frequently the common paint is sold under this name, when accidentally the color turns out a. little better than usual. If made from the distilled verdigris, it need not be passed through a sieve, either wet or dry, because there are no impurities to be removed.
The above is not the simplest manner of operating. However, it is the best, as by the slowness of the process the crystallization goes on without disturbance, which always interferes with perfect crystallization.
If the latter is not considered essential, one may perform the operation by dissolving the arsenic in the large kettle in the proportions given above, and then adding the verdigris paste; and either draw off at once, when the yellowish-green precipitate takes the right color already during the pouring, or it may first be boiled for a short time, when all time color is formed in time kettle, from which it is afterward drawn, or the verdigris may be pulverized, passed through a sieve and mixed in the arsenic solution, or the boiling solution may be poured into time powdered verdigris. Every variation of time methodus operandi will give as result a different shade in the green paint obtained.
13.7.14
Paints made of Copper. Mountain Green and Blue, (Berg Green). Neuwieder Green, Neuwieder Blue.
Manufacturer and builder Volume 4, 1871
We have mentioned, on page 142 of our second volume, that the minerals malachite and lazulite are beautiful green and blue carbonates of copper, (or cupric carbonates, according to the new nomenclature,) but rather expensive minerals to crush and use as paints; this was only done in olden times, before chemistry had taught us how to manufacture a much brighter and purer compound of the same composition, and it is at present, perhaps, impossible to obtain a good green or blue copper paint not artificially made, but of real mineral origin.
The natural carbonate of copper is the oldest green color known: the artificial article is also the oldest green color made by chemists. Soon, however, the so-called mineral green, when made artificially, had nothing in common with the natural green but the color and the fact that it was made from copper A carbonate was no longer made, because experience had taught that other compounds of copper could be made cheaper and of a finer color than the imitation malachite or carbonate. The paints now in the market, and sold under the name of mineral green, are, in reality, different combinations of copper, made in different ways, and imitated in a great variety of styles.
The oldest method was to take a warm solution of cupric sulphate free from iron, precipitate the copper as carbonate by adding a small excess of potassic carbonate, and wash and dry the latter. This powdered precipitate was by no means a brilliant paint; but when used with oil, it became gradually of a darker and more beautiful color. A later method was to take 100 pounds of cupric sulphate, 2 pounds of potassic tartrate dissolved in at least 600 pounds of water, and precipitated with a solution of 21 pounds arsenious acid, and 10 to 12 pounds of potash dissolved in about 600 pounds of water; then add 22 pounds of lime mixed with water, to form a milk of lime; and finally 60 pounds of very finely-ground heavy-spar. Wash and filter the precipitate; press in the ferns of cakes, and dry. By keeping for a long time, the color improves considerably.
It is seen that this method is identical with that described before, on page 85, for Braunschweiger green, only it contains more arsenic, and has therefore a better color. It is now sold in Germany under the name of Neuwider green. Sometimes Schweinfurter green, a similar compound, is mixed with it. So it is seen that, in fact, the so-called mineral greens at present in the trade are nothing but hydrated cupric oxide with an excess of lime, chalk, and heavy-spar, owing their fine color to the addition of cupric ar-senile and acetate.
These mineral greens may be used as water or oil. paints, but the finest kinds can not well be used on lime, while the Schweinfurter green, for example, under such circumstances, changes its color into a, greenish. yellow. It often contains, besides, an adulteration of calcic sulphate, or gypsum. Its value, therefore, is best tested by mixing it with white. The kinds which can stand the largest amount of white with the least amount of change to a paler green are the best. Chemically, however, the test is easy; all we have to do is to digest the powder with a solution of ammonium chloride (sal ammoniac) or with liquid ammonia, which will slowly dissolve all the copper and leave a residue of lime, heavy-spar, etc., which may be then dried and weighed. Of course, the larger this residue, the lower the value of the paint. The amount of copper is sometimes found to be as low as fifteen per cent.
Neuwieder Green, Neuwieder Blue.
One way of making this green is the same as in making the mineral green (p. 60) or the Braun-schweiger green, (p. 35,) and its tint may be varied by varying the amount of arsenious acid employed.
A better and improved way of making this green of a far superior quality was for a long time a secret of a few manufacturers, but, as in the case with all such secrets, in the course of time it became known. To make it they took a solution of blue vitriol, and added liquid ammonia gradually, till the precipitate formed at first was redissolved again, and a pure dark-blue liquid was obtained; to this was added milk of lime, stirring continually, till a small quantity of a precipitate appeared; then the warns liquid was filtered and cooled, when long, fine, needle-like crystals were formed, which were the concentrated blue coloring material, and of a most brilliant appearance. These have only to be mixed with an excess of lime, strained, and dried to make the Neuwieder blue.
To change it into green after the improved secret method, this blue, when still wet, is mixed with a cold solution of arsenious acid till changed to the right shade, which is totally under the command of the operator, by regulating the quantity of arsenic. After straining, pressing, and drying the deposit, it is kept in large vessels in cellars, where it slowly obtains a much finer and purer color, which penetrates from the outside of the pieces to the interior.
A third cheaper method, adapted to localities where acetic acid or acetate of lime is cheap, is the following:
80 pounds of calcic acetate, (acetate of lime,) or an equivalent mixture of acetic acid and slacked lime, (40 pounds of the acid and 30 dry lime,) is mixed with water and boiled in a vessel with 100 pounds arsenious acid, which is not dissolved, but combines in such a way that we obtain arsenite of lime and diluted acetic acid. Then 125 pounds of cupric sulphate is gradually added, stirring the mixture often. At first we obtain a yellowish color, which, however, after the addition of all the cupric sulphate, becomes a bluish green. As soon as this change is seen, the fire is extinguished, the liquid drawn off into another vessel and cooled, when the green paint is deposited, which is removed without washing, and dried in irregular pieces. To this paint pulverized heavy-spar is also frequently added as an adulteration.
Common vinegar may also be used in the preparation, but then the color has never the freshness and beauty given by using acetic acid; but the most essential condition, in all these, preparations, is, that the blue vitriol be totally free from iron, the smallest quantity of which greatly deteriorates the beauty of the paint.
It must be mentioned that the liquid drawn off still contains copper and acetic acid, which, however, may be utilized in the next operation.
When pure lime can not be obtained, but only a lime which is clayey or sandy, it is better to use fine chalk or ground Iceland spar, (calcic carbonate.) It requires then, however, 5 parts for every 3 of lime, in order to obtain the same results, because the atomic weight of carbonic acid is combined with the lime so that 50 parts only contain 30 of lime. The only inconvenience is the evolution of carbonic acid, which makes the liquid foam and run over when not mixed carefully and slowly.
A fourth method, adapted to localities where acetic acid or acetate of lime is scarce but French verdigris cheap, is the following:
100 pounds arsenious acid are boiled with a sufficient quantity of water 3 to 4 hours, or till dissolved. Then 70 pounds of ground hydrated white gypsum are mixed in, and immediately afterward a paste con-sisting of 100 pounds verdigris mixed with the required water. The formation of the paint takes place, as in the former cases. The liquid is drained off, the heavy-spar mixed in, in case the adulteration is desired, all well mixed, passed through a sieve, in order to separate the impurities of the verdigris on the sieve. This method gives for the quantities mentioned 170 pounds of pure green paint, which may be adulterated to suit circumstances.
The liquid drawn off contains some green in solu-tion; also arsenious acid, and free acetic acid. It may be again used for dissolving the arsenic in the next operation; but then it is only necessary to use 60 pounds arsenic instead of 100 pounds, about 25 pounds cupric sulphate, and a milk of lime of only 6 pounds fresh-burnt lime, after the 100 pounds of verdigris have been added. If the liquid is impure, or for some other reason can not be utilized in this way, it may be precipitated by potash or soda, and thus a clear green paint obtained, adapted to be added to mineral green.
This is a good water-color, but difficult to rub up fine in oil; there is not much body to it. On lime it can not be used, its acetic acid being abstracted, making it yellow. Otherwise its tone is much brighter than all the others of this class before described.
To determine the adulteration and value of a sample by analysis, the simplest way is to treat it cold with hydrochloric acid till the remnant is white. The liquid is then filtered to separate it from the remnant, the filter washed, and the filtrate treated with caustic potash till dissolved, then boiled till the precipitate is black, filtered, washed, dried, and weighed.
Being oxide of copper, its weight will show which paint contained the most copper and hiss the greatest value, as its price increases in the same ratio as the amount of copper contained in it.
We have mentioned, on page 142 of our second volume, that the minerals malachite and lazulite are beautiful green and blue carbonates of copper, (or cupric carbonates, according to the new nomenclature,) but rather expensive minerals to crush and use as paints; this was only done in olden times, before chemistry had taught us how to manufacture a much brighter and purer compound of the same composition, and it is at present, perhaps, impossible to obtain a good green or blue copper paint not artificially made, but of real mineral origin.
The natural carbonate of copper is the oldest green color known: the artificial article is also the oldest green color made by chemists. Soon, however, the so-called mineral green, when made artificially, had nothing in common with the natural green but the color and the fact that it was made from copper A carbonate was no longer made, because experience had taught that other compounds of copper could be made cheaper and of a finer color than the imitation malachite or carbonate. The paints now in the market, and sold under the name of mineral green, are, in reality, different combinations of copper, made in different ways, and imitated in a great variety of styles.
The oldest method was to take a warm solution of cupric sulphate free from iron, precipitate the copper as carbonate by adding a small excess of potassic carbonate, and wash and dry the latter. This powdered precipitate was by no means a brilliant paint; but when used with oil, it became gradually of a darker and more beautiful color. A later method was to take 100 pounds of cupric sulphate, 2 pounds of potassic tartrate dissolved in at least 600 pounds of water, and precipitated with a solution of 21 pounds arsenious acid, and 10 to 12 pounds of potash dissolved in about 600 pounds of water; then add 22 pounds of lime mixed with water, to form a milk of lime; and finally 60 pounds of very finely-ground heavy-spar. Wash and filter the precipitate; press in the ferns of cakes, and dry. By keeping for a long time, the color improves considerably.
It is seen that this method is identical with that described before, on page 85, for Braunschweiger green, only it contains more arsenic, and has therefore a better color. It is now sold in Germany under the name of Neuwider green. Sometimes Schweinfurter green, a similar compound, is mixed with it. So it is seen that, in fact, the so-called mineral greens at present in the trade are nothing but hydrated cupric oxide with an excess of lime, chalk, and heavy-spar, owing their fine color to the addition of cupric ar-senile and acetate.
These mineral greens may be used as water or oil. paints, but the finest kinds can not well be used on lime, while the Schweinfurter green, for example, under such circumstances, changes its color into a, greenish. yellow. It often contains, besides, an adulteration of calcic sulphate, or gypsum. Its value, therefore, is best tested by mixing it with white. The kinds which can stand the largest amount of white with the least amount of change to a paler green are the best. Chemically, however, the test is easy; all we have to do is to digest the powder with a solution of ammonium chloride (sal ammoniac) or with liquid ammonia, which will slowly dissolve all the copper and leave a residue of lime, heavy-spar, etc., which may be then dried and weighed. Of course, the larger this residue, the lower the value of the paint. The amount of copper is sometimes found to be as low as fifteen per cent.
Neuwieder Green, Neuwieder Blue.
One way of making this green is the same as in making the mineral green (p. 60) or the Braun-schweiger green, (p. 35,) and its tint may be varied by varying the amount of arsenious acid employed.
A better and improved way of making this green of a far superior quality was for a long time a secret of a few manufacturers, but, as in the case with all such secrets, in the course of time it became known. To make it they took a solution of blue vitriol, and added liquid ammonia gradually, till the precipitate formed at first was redissolved again, and a pure dark-blue liquid was obtained; to this was added milk of lime, stirring continually, till a small quantity of a precipitate appeared; then the warns liquid was filtered and cooled, when long, fine, needle-like crystals were formed, which were the concentrated blue coloring material, and of a most brilliant appearance. These have only to be mixed with an excess of lime, strained, and dried to make the Neuwieder blue.
To change it into green after the improved secret method, this blue, when still wet, is mixed with a cold solution of arsenious acid till changed to the right shade, which is totally under the command of the operator, by regulating the quantity of arsenic. After straining, pressing, and drying the deposit, it is kept in large vessels in cellars, where it slowly obtains a much finer and purer color, which penetrates from the outside of the pieces to the interior.
A third cheaper method, adapted to localities where acetic acid or acetate of lime is cheap, is the following:
80 pounds of calcic acetate, (acetate of lime,) or an equivalent mixture of acetic acid and slacked lime, (40 pounds of the acid and 30 dry lime,) is mixed with water and boiled in a vessel with 100 pounds arsenious acid, which is not dissolved, but combines in such a way that we obtain arsenite of lime and diluted acetic acid. Then 125 pounds of cupric sulphate is gradually added, stirring the mixture often. At first we obtain a yellowish color, which, however, after the addition of all the cupric sulphate, becomes a bluish green. As soon as this change is seen, the fire is extinguished, the liquid drawn off into another vessel and cooled, when the green paint is deposited, which is removed without washing, and dried in irregular pieces. To this paint pulverized heavy-spar is also frequently added as an adulteration.
Common vinegar may also be used in the preparation, but then the color has never the freshness and beauty given by using acetic acid; but the most essential condition, in all these, preparations, is, that the blue vitriol be totally free from iron, the smallest quantity of which greatly deteriorates the beauty of the paint.
It must be mentioned that the liquid drawn off still contains copper and acetic acid, which, however, may be utilized in the next operation.
When pure lime can not be obtained, but only a lime which is clayey or sandy, it is better to use fine chalk or ground Iceland spar, (calcic carbonate.) It requires then, however, 5 parts for every 3 of lime, in order to obtain the same results, because the atomic weight of carbonic acid is combined with the lime so that 50 parts only contain 30 of lime. The only inconvenience is the evolution of carbonic acid, which makes the liquid foam and run over when not mixed carefully and slowly.
A fourth method, adapted to localities where acetic acid or acetate of lime is scarce but French verdigris cheap, is the following:
100 pounds arsenious acid are boiled with a sufficient quantity of water 3 to 4 hours, or till dissolved. Then 70 pounds of ground hydrated white gypsum are mixed in, and immediately afterward a paste con-sisting of 100 pounds verdigris mixed with the required water. The formation of the paint takes place, as in the former cases. The liquid is drained off, the heavy-spar mixed in, in case the adulteration is desired, all well mixed, passed through a sieve, in order to separate the impurities of the verdigris on the sieve. This method gives for the quantities mentioned 170 pounds of pure green paint, which may be adulterated to suit circumstances.
The liquid drawn off contains some green in solu-tion; also arsenious acid, and free acetic acid. It may be again used for dissolving the arsenic in the next operation; but then it is only necessary to use 60 pounds arsenic instead of 100 pounds, about 25 pounds cupric sulphate, and a milk of lime of only 6 pounds fresh-burnt lime, after the 100 pounds of verdigris have been added. If the liquid is impure, or for some other reason can not be utilized in this way, it may be precipitated by potash or soda, and thus a clear green paint obtained, adapted to be added to mineral green.
This is a good water-color, but difficult to rub up fine in oil; there is not much body to it. On lime it can not be used, its acetic acid being abstracted, making it yellow. Otherwise its tone is much brighter than all the others of this class before described.
To determine the adulteration and value of a sample by analysis, the simplest way is to treat it cold with hydrochloric acid till the remnant is white. The liquid is then filtered to separate it from the remnant, the filter washed, and the filtrate treated with caustic potash till dissolved, then boiled till the precipitate is black, filtered, washed, dried, and weighed.
Being oxide of copper, its weight will show which paint contained the most copper and hiss the greatest value, as its price increases in the same ratio as the amount of copper contained in it.
12.7.14
Paints Made of Copper. Mineral green, Paris Green, or Emerald Green.
Manufacturer and builder 3, 1871
There is a class of bright green paints in the trade, which are all a combination of copper and arsenic, with some lime, potash, etc., in different proportions, and which, chemically considered, should bear the name of arsenite of copper; in time common language of the trade they bear different names in different localities, and these are still more varied by their shade of color, which often depends on a trifle during time preparation. Besides the names mentioned at time head of this article, which are time most common in this part of time world, they are called Schweinfurter green, after the German city where it was first manufactured; Scheele's green, after the eminent chemist who first discovered it; Saalfeld, Vienna, Cassel green, after different cities from whence it may be obtained; new green, as once it was a novelty; kaiser, or imperial green, as it is time most brilliant of all greens; in fact, there exists time greatest confusion imaginable in regard to time names given to these paints. All differ slightly, and ought only to be judged by close inspection.
The original green as made by Scheele, in Sweden, comes into time trade in broad, irregular tabular pieces, but differs in tone from bright green to a very deep color. The fracture is conchoidal, (like a shell,) and possesses in time darker varieties a beautiful brown lustre. It is very brittle, and when powdered much lighter in color. In manufacturing the different shades, there is no difference in time method except in the quantity of arsenic, a larger proportion of which makes it lighter, until finally, by excess of arsenic, it becomes yellowish green. As the copper paints are naturally bluish-green, it is seen that the arsenic counteracts this, as it has a tendency to make yellow compounds - for instance, orpiment, which is a com-pound of arsenic and sulphur.
To make Paris green, take 10 parts cupric sulphate, (blue vitriol,) dissolve in about 50 parts water, let the solution settle till clear, and draw it off into a vessel which has previously been filled with about 100 parts of water.
Then take 9 parts of pure calcined potash, and 5 parts of quicklime, and make a caustic lye of time strength of about 15° to 20° of time hydrometer; separate the clear solution from time deposit of lime.
Then take 1 part arsenious acid, and 2 parts calcined potash, dissolve them together with sufficient water, by boiling in a copper vessel, let it settle, and pour off time clear liquid.
Then pour time arsenic solution in that of the cupric sulphate, stir well, and add the caustic lye; a precipitate will be formed, which is the paint desired, and which by washing is purified from the adhering caustic liquid. This washing must be repeated three to six times; then time precipitate is dried in a warm place upon linen filters, in layers of less than half an inch thick, which are afterward pressed. Warmth improves the appearance and lustre.
We suggest that soda, and even the crystallized carbonate, or so-called washing-soda, which is at present so cheap in this country, may be used in place of time potash. Fourteen parts of time same may supplant the nine parts of potash mentioned, the same amount of lime to be used.
From the amount of ingredients mentioned, we obtain about 5 parts dry paint. It is seldom adulterated, as it can not stand it. It loses its lustre and peculiar fracture by time addition of white; also it is very difficult to divide the white adulteration so well that it can not be seen on the fracture. The only adulteration possible is with barytic-sulphate, (heavy spar;) and this is easily found by dissolving time paint in nitric acid, when the heavy spar will remain undissolved. When it is required to ascertain the amount of the adulteration, time spar must be digested with liquid ammonia, to purify it, then dried and weighed.
This paint is the original Scheele's green, and so, called in Sweden; but what at the present day is called in Germany and the United States Scheele's green, is made by simply dissolving, in a solution of 9 parts calcined potash, about 3 to 4 parts of arsenic, more or less according to tint desired, and throwing it in a boiling solution of 10 parts of cupric-sulphate, which must contain no iron. After stirring well, it is left to settle, and the precipitate is washed and dried. It is used as a water-color, oil-color, and as a lime-color.
There is a class of bright green paints in the trade, which are all a combination of copper and arsenic, with some lime, potash, etc., in different proportions, and which, chemically considered, should bear the name of arsenite of copper; in time common language of the trade they bear different names in different localities, and these are still more varied by their shade of color, which often depends on a trifle during time preparation. Besides the names mentioned at time head of this article, which are time most common in this part of time world, they are called Schweinfurter green, after the German city where it was first manufactured; Scheele's green, after the eminent chemist who first discovered it; Saalfeld, Vienna, Cassel green, after different cities from whence it may be obtained; new green, as once it was a novelty; kaiser, or imperial green, as it is time most brilliant of all greens; in fact, there exists time greatest confusion imaginable in regard to time names given to these paints. All differ slightly, and ought only to be judged by close inspection.
The original green as made by Scheele, in Sweden, comes into time trade in broad, irregular tabular pieces, but differs in tone from bright green to a very deep color. The fracture is conchoidal, (like a shell,) and possesses in time darker varieties a beautiful brown lustre. It is very brittle, and when powdered much lighter in color. In manufacturing the different shades, there is no difference in time method except in the quantity of arsenic, a larger proportion of which makes it lighter, until finally, by excess of arsenic, it becomes yellowish green. As the copper paints are naturally bluish-green, it is seen that the arsenic counteracts this, as it has a tendency to make yellow compounds - for instance, orpiment, which is a com-pound of arsenic and sulphur.
To make Paris green, take 10 parts cupric sulphate, (blue vitriol,) dissolve in about 50 parts water, let the solution settle till clear, and draw it off into a vessel which has previously been filled with about 100 parts of water.
Then take 9 parts of pure calcined potash, and 5 parts of quicklime, and make a caustic lye of time strength of about 15° to 20° of time hydrometer; separate the clear solution from time deposit of lime.
Then take 1 part arsenious acid, and 2 parts calcined potash, dissolve them together with sufficient water, by boiling in a copper vessel, let it settle, and pour off time clear liquid.
Then pour time arsenic solution in that of the cupric sulphate, stir well, and add the caustic lye; a precipitate will be formed, which is the paint desired, and which by washing is purified from the adhering caustic liquid. This washing must be repeated three to six times; then time precipitate is dried in a warm place upon linen filters, in layers of less than half an inch thick, which are afterward pressed. Warmth improves the appearance and lustre.
We suggest that soda, and even the crystallized carbonate, or so-called washing-soda, which is at present so cheap in this country, may be used in place of time potash. Fourteen parts of time same may supplant the nine parts of potash mentioned, the same amount of lime to be used.
From the amount of ingredients mentioned, we obtain about 5 parts dry paint. It is seldom adulterated, as it can not stand it. It loses its lustre and peculiar fracture by time addition of white; also it is very difficult to divide the white adulteration so well that it can not be seen on the fracture. The only adulteration possible is with barytic-sulphate, (heavy spar;) and this is easily found by dissolving time paint in nitric acid, when the heavy spar will remain undissolved. When it is required to ascertain the amount of the adulteration, time spar must be digested with liquid ammonia, to purify it, then dried and weighed.
This paint is the original Scheele's green, and so, called in Sweden; but what at the present day is called in Germany and the United States Scheele's green, is made by simply dissolving, in a solution of 9 parts calcined potash, about 3 to 4 parts of arsenic, more or less according to tint desired, and throwing it in a boiling solution of 10 parts of cupric-sulphate, which must contain no iron. After stirring well, it is left to settle, and the precipitate is washed and dried. It is used as a water-color, oil-color, and as a lime-color.
11.7.14
Paints Made of Copper. Chlor Copper Oxide. Braunschweiger green.
Manufacturer and builder Volume 2, 1871
Chlor Copper Oxide
There aro different compounds of chloride of copper and oxide of copper, or cupric chloride and cupric oxide, as the now nomenclature has it. One of thew, however, is exclusively used either as a paint or as a material for the manufacture of other paints. It i s made in the following manner:
One hundred pounds of cupric sulphate (blue vitriol) are moistened and ground up in a paint-mill with sixty punds of sodium chloride, (common salt,) so as to obtain a pasty mass, consisting, by mutual decomposition, of natrium sulphate and cupricchloride, with an excess or remnant of common salt. This mass is now used to act on three hundred pounds metallic copper. For this purpase, pure cheat copper is cleaned and cut up in small stripes, which are placed in alternate layers with the mass previously described, is flat vessels, and put in a place such as a cellar, where the temperature is uniform. They aro kept there about three months being stirred about once a week. The result will finally be that the cupric chloride Cu Cl2 in the pasty mass, by combining with more metallic copper, will be changed into cuproud chloride, Cu2 Cl2. The first is a yellowish, brown deliquescent substance; the latter whitish, becoming blue on exposure to the air, whence it absorbs oxygen; and the action continues till all the cupric chloride, Cu Cl2, has come in contact with so much copper that it is changed, first into Cu2 Cl2, and then into the insoluble chlor copper oxide, Cu Cl+Cu O. The test, therefore, for determining when the operation ia completed, is to throw some of the mass in water. As long as green solution is formed, the operiation is continued, and only suspended when the water remains clear. The blu-green powder is now separated by means of a sieve from the remaining strips of metallic copper, which are utilized in the next operation. The true formula of the compund is this:
Cu Cl +2Cu O +5 H O,
which, according to chemical equivalents, would give
(64+36) +2(64+16) +5(1+8),
or 100 + 16+ + 45,
which agrees well with the analysis of the substance, which given for 100 parts,
32 Cuproid chloride ... Cu Cl.
53 Cuprous oxide ... Cu O
15 Water ... HO
----
100
It behaves, with referrance to foreign substances, like other salts of copper; but has the advantage of containing only one quarter as much acid; for which reason, by precipitation by means of alkalies, copper oxide can be obtained in the most economical manner. Formally, green paste was used as a paint, and the so-called Braunschweiger green was made of the same, after it was partially changed into hydrated oxide of copper. This paint is now made by another method, which we will now describe, remarking, however, that the demand for it has of late years considerably diminished.
Braunschweiger green
One hundred pound., cupric sulphate (blue vitriol) are dissolved tartrate an abundance of water and 2 pounds of potassic tartrate (salts of tartar) in a copper vessel. Three ounces of arsenious acid are also dissolved in water, with 10 pounds calcined potash in another copper vessel. Twenty-two pounds fresh burnt lime, which keeps a pure white color when slacked with water, are mixed with more water till a milk of lime is formed, left for a few days, and, when stiffened, well ground up in a paint-mill. The copper solution first mentioned is then precipitated, stirring it continually, by first pouring in the potassic arsenite solution, and the nthe milk of lime. After settling, the supernatant water is drawn off, and the precipitate washed with more water.
The common kinds used to be adulterated with ground barium sulphate, (heavy spar.) By adding 60 pounds of this material to the above, from 135 to 140 pounds of paint are obtained. This mass is pressed into long rectangular cakes, then cut and dried in the air.
It may be used as water-color, oil-paint, and for fresco. As lime-color, however, it is pale, and has little intensity. Used as an oil-paint, it at first looks pale, but becomes continually darker; as is also the case with the Bremen blue, described in Vol. II., pp. 142, 238, and at last ends with being a very beautiful green. We ought to remark that, in some localities, Bremen blue is called Braunschweiger green.
Chlor Copper Oxide
There aro different compounds of chloride of copper and oxide of copper, or cupric chloride and cupric oxide, as the now nomenclature has it. One of thew, however, is exclusively used either as a paint or as a material for the manufacture of other paints. It i s made in the following manner:
One hundred pounds of cupric sulphate (blue vitriol) are moistened and ground up in a paint-mill with sixty punds of sodium chloride, (common salt,) so as to obtain a pasty mass, consisting, by mutual decomposition, of natrium sulphate and cupricchloride, with an excess or remnant of common salt. This mass is now used to act on three hundred pounds metallic copper. For this purpase, pure cheat copper is cleaned and cut up in small stripes, which are placed in alternate layers with the mass previously described, is flat vessels, and put in a place such as a cellar, where the temperature is uniform. They aro kept there about three months being stirred about once a week. The result will finally be that the cupric chloride Cu Cl2 in the pasty mass, by combining with more metallic copper, will be changed into cuproud chloride, Cu2 Cl2. The first is a yellowish, brown deliquescent substance; the latter whitish, becoming blue on exposure to the air, whence it absorbs oxygen; and the action continues till all the cupric chloride, Cu Cl2, has come in contact with so much copper that it is changed, first into Cu2 Cl2, and then into the insoluble chlor copper oxide, Cu Cl+Cu O. The test, therefore, for determining when the operation ia completed, is to throw some of the mass in water. As long as green solution is formed, the operiation is continued, and only suspended when the water remains clear. The blu-green powder is now separated by means of a sieve from the remaining strips of metallic copper, which are utilized in the next operation. The true formula of the compund is this:
Cu Cl +2Cu O +5 H O,
which, according to chemical equivalents, would give
(64+36) +2(64+16) +5(1+8),
or 100 + 16+ + 45,
which agrees well with the analysis of the substance, which given for 100 parts,
32 Cuproid chloride ... Cu Cl.
53 Cuprous oxide ... Cu O
15 Water ... HO
----
100
It behaves, with referrance to foreign substances, like other salts of copper; but has the advantage of containing only one quarter as much acid; for which reason, by precipitation by means of alkalies, copper oxide can be obtained in the most economical manner. Formally, green paste was used as a paint, and the so-called Braunschweiger green was made of the same, after it was partially changed into hydrated oxide of copper. This paint is now made by another method, which we will now describe, remarking, however, that the demand for it has of late years considerably diminished.
Braunschweiger green
One hundred pound., cupric sulphate (blue vitriol) are dissolved tartrate an abundance of water and 2 pounds of potassic tartrate (salts of tartar) in a copper vessel. Three ounces of arsenious acid are also dissolved in water, with 10 pounds calcined potash in another copper vessel. Twenty-two pounds fresh burnt lime, which keeps a pure white color when slacked with water, are mixed with more water till a milk of lime is formed, left for a few days, and, when stiffened, well ground up in a paint-mill. The copper solution first mentioned is then precipitated, stirring it continually, by first pouring in the potassic arsenite solution, and the nthe milk of lime. After settling, the supernatant water is drawn off, and the precipitate washed with more water.
The common kinds used to be adulterated with ground barium sulphate, (heavy spar.) By adding 60 pounds of this material to the above, from 135 to 140 pounds of paint are obtained. This mass is pressed into long rectangular cakes, then cut and dried in the air.
It may be used as water-color, oil-paint, and for fresco. As lime-color, however, it is pale, and has little intensity. Used as an oil-paint, it at first looks pale, but becomes continually darker; as is also the case with the Bremen blue, described in Vol. II., pp. 142, 238, and at last ends with being a very beautiful green. We ought to remark that, in some localities, Bremen blue is called Braunschweiger green.
10.7.14
Paints Made of Copper. - Distilled Verdigris.
Manufacturer and builder 1, 1871
The so-called distilled, or rather crystallized, verdigris was formerly produced in France, but now also in many other countries, in a variety of ways. The main condition, however, necessary for its production on a large scale and in a profitable manner is a cheap supply of pure vinegar. The old method of making dis-tilled verdigris is to dissolve the impure verdigris in an excess of distilled vinegar. The liquid is then slowly evaporated in copper pans, in order to crystallize it in the same way as the solutions of acetate of copper hereafter described.
A solution of the acetate of copper may be also obtained by decomposing a solution of sulphate of copper (blue vitriol) by acetate of lead (lead-sugar) or acetate of baryta. The metals interchange their acids, not on account of greater chemical affinity of a base for a certain acid, as most text-books in chemistry still teach, but for the simple reason that by this change an in-soluble compound can be formed. The force of cohesion of the molecules of this insoluble sulphate of lead is greater than that of the soluble sulphate of copper, and hence the lead yields up its acetic acid, which forms with it a soluble compound, and takes possession of the sulphuric acid which was combined with the copper, forming in this way an insoluble sulphate of lead. The free acetic acid then immediately attacks the oxide of copper, old forms with it an acetate of copper, which remains in solution while the sulphate of lead is precipitated.
It is a well-established chemical law that, whenever the interchange of the acids of two soluble chem-ical compounds will cause one of the bases to unite with the acid previously combined with the other base, and form an insoluble compound, this reaction always takes place whenever the solutions are brought together, regardless of the chemical affinities of the two bases. As this law explains many chemical phenomena formerly supposed to be rather strange, we think it worth while to direct our readers' attention to it.
There are several other ways of producing the solution of the acetate of copper; but as the salts required are not as cheap as those mentioned, the old process is still preferred. It is not necessary to use the crystallized blue vitriol or the lead-sugar. The pure concentrated solutions may be made from the copper and lead, and used in place of the solutions made from the crystallized salts. There is no difference in the result, whether lead-sugar or acetate of baryta is used, except that in the first case the incidental product is the precipitate of sulphate of lead, a substitute for white-lead, and in the second case, sulphate of baryta, or heavy spar, a substance largely used for adulterating white-lead.
To produce the precipitate in the best manner, the solution of the acetate is slightly heated, placed in the precipitating vessel and constantly stirred, while the solution of sulphate of copper is slowly added. A white precipitate immediately commences to fall down, and the addition of the copper solution is continued as long as it produces any precipitate; consequently it must be added with care toward the end of the operation, in order to avoid an excess of the copper solu-tion. If an excess has been added, a quantity of the acetate solution must be added slowly till this fails to produce a precipitate, so that we may be sure that no excess of either salt is present. In order to test this more fully, a small quantity of the mixture is filtered into a test-glass, and a few drops of either solution added. If a few drops of one produce a cloudiness, we know that we have added too much of the other to the mixture. The intensity of this cloudiness indicates to the experienced workman the amount of the solution which must be added to the mixture to avoid an excess of either salt. When the required correc-tions have been made, the solution is allowed to settle for several hours, so that the supernatant fluid is perfectly clear. This is then drawn off by copper or wooden stop-cocks at the side of the vessel, or by means of siphons. This liquid is then placed in large copper pans, and evaporated at a temperature of 140° to 180° Fahr. As soon as a small portion of the liquid, taken out by: means of a small dipper and cooled, commences to deposit crystals, the fires are withdrawn from under the pans, and strings and sticks are suspended in the liquid. On cooling, crystals of verdigris will deposit themselves upon the sticks and strings as well as on the bottom and sides of the pans.
In the paint manufactories, when the acetate of copper is used for other purposes, the solution is used but not concentrated and crystallized. In this case, the question arises, How much crystallized verdigris is contained in a given quantity, for instance, in ten gallons of the solution? There are, of course, very correct chemical methods of determining this point, but these are not as useful for practical purposes as the following simple method, which is, therefore, universally adopted.
The specific gravity of the solution is ascertained by means of Beaumes hydrometer, and the temperature noted; then a small quantity of pure acetate of cop-per, say one pound, is dissolved in as little water as possible, and then water added till a solution is obtained of the same specific gravity and temperature as the solution, of which the degree of concentration is required. By partially immersing the vessels contain-ing the concentrated solution of the crystals, and the water with which it is to be diluted, in the original solution, the equality of temperature is easily obtained. Suppose now that the pound of acetate of copper has been dissolved in a quart of water, in order to bring it to the sane specific gravity as the ten gallons of solution to be tested, it is clear that both solutions would contain acetate of copper at the rate of four pounds per gallon, or forty pounds in the ten gallons.
Some manufacturers do not make the acetate and copper salts, but buy them in crystallized form. For the benefit of these, it is easy to give, once for all, the relative amount of material required to produce a given quantity of verdigris without excess or loss of either material, or without requiring the trouble of testing whether there is any excess of one or the other of the generating salts. According to the theory of chemical equivalents, a solution of one hundred and twenty-five parts, by weight, of sulphate of copper has to be mixed with a solution of one hundred and ninety of lead-sugar, or one hundred and fifty-four and a half of crystallized acetate of baryta, in order to form a complete decomposition, and time recomposition of, theoretically, exactly one hundred pounds of crystallized verdigris, with a precipitate of two hundred and fifteen pounds of sulphate of lead, or one hundred and seventy-five and a half pounds of sulphate of baryta.
Practically, however, the lead or baryta precipitate carries down with it some of the acetate of copper, and both have therefore a greenish color; there is, there-fore, some loss of acetate of copper. By repeatedly washing the precipitate, it may be purified from the adhering verdigris. In this way the precipitate becomes more valuable, while the water used for the washing, and containing some of the copper compound, may be used for the succeeding solutions, and in this nranner the verdigris may also be saved.
Recently, it has become possible to obtain acetate of soda, in crystals or in solution, in large quantities and at low prices, and this gives occasion to another economical way of making a concentrated solution of acetate of copper. The acetate of soda may be obtained by saturating one hun-dred and forty-four parts of crystallized soda with vinegar, filtering through animal carbon in case it is colored, and concentrating by evaporation. Then one hundred and twenty-five parts of sul-phate of copper are dissolved in the same, and a clear solution will be obtained, in which the soda, the copper, the acetate and sulphuric acid are present, but from which a large quantity of acetate of copper may be obtained by crystallization. The strong tendency of this substance to crystallize being in this case the cause of the combination of the copper with the acetic acid, the sulphate of soda, which is very soluble, and hence does not crystallize so easily, will remain in the solution. This solution may, however, be used for many purposes without crystallization.
Also, if twenty-nine parts of pure quick lime are slacked with water, and dissolved in vinegar, the solution concentrated by evaporation, and mixed with a solution of one hundred and twenty-five parts of sulphate of copper, we obtain a precipitate of sulphate of lime, (plaster of Paris, gypsum,) and a solution of acetate of copper, which may be easily separated from the precipitate by decantation and filtration. However, as the gypsum is slightly soluble in water, (one part gypsum in three hundred of cold water) the solution will contain it in this ratio, and can therefore only be used to produce a color less brilliant than that made from pure verdigris. The great trouble in this case is, that the gypsum is less soluble in warm water than in cold water, and that by heating the solution for crystallization the gypsum is deposited with the crystals of verdigris.
Crystallized acetate of copper is also not very soluble in cold water. Four hundred parts of water will dissolve only one part of the crystals. It is, however, much more soluble in hot water; but if boiled for some time it is decomposed, some of the acetic acid being driven off, and causing the solution to become turbid. A bluish basic salt, that is to say, a compound which contains a double amount of copper oxide, is thrown down. Its production may be avoided by never heat ing the solutions to the boiling-point, but keeping them at a temperature between 140° and 180° Fahr., as mentioned above.
The crystallized acetate of copper is seldom used as a paint, while the basic impure verdigris described in our former number (page 334) is much more adapted for this purpose. It comists of forty per cent of oxide of copper, fifty-one per cent of acetic acid, and nine of water. Its chemical formula is Cu O, (C4H3O3) +HO, which expresses most beautifully this composition according to the definite amount of matter expressed by each symbol. Cu always represents thirty-two parts of copper; O, eight parts of oxygen; C, six parts of carbon; H, one of hydrogen; and for the benefit of students in chemistry, we close this article on the most important of all copper compounds for the ma-nufacture of paints, with a simple calculation of the amount of each ingredient entering in its composition.
It serves at the same time as an illustration of what was commenced to be taught in a former number of The Manufacturer and Builder.
Oxide of Copper, (Cu O) = 32+8 =40
Acetic acid (C4H3O3)=4 x 6+3+3 x 8 =51
Water, (HO)=1+8 = 9
Acetate of copper, Total, 100
The so-called distilled, or rather crystallized, verdigris was formerly produced in France, but now also in many other countries, in a variety of ways. The main condition, however, necessary for its production on a large scale and in a profitable manner is a cheap supply of pure vinegar. The old method of making dis-tilled verdigris is to dissolve the impure verdigris in an excess of distilled vinegar. The liquid is then slowly evaporated in copper pans, in order to crystallize it in the same way as the solutions of acetate of copper hereafter described.
A solution of the acetate of copper may be also obtained by decomposing a solution of sulphate of copper (blue vitriol) by acetate of lead (lead-sugar) or acetate of baryta. The metals interchange their acids, not on account of greater chemical affinity of a base for a certain acid, as most text-books in chemistry still teach, but for the simple reason that by this change an in-soluble compound can be formed. The force of cohesion of the molecules of this insoluble sulphate of lead is greater than that of the soluble sulphate of copper, and hence the lead yields up its acetic acid, which forms with it a soluble compound, and takes possession of the sulphuric acid which was combined with the copper, forming in this way an insoluble sulphate of lead. The free acetic acid then immediately attacks the oxide of copper, old forms with it an acetate of copper, which remains in solution while the sulphate of lead is precipitated.
It is a well-established chemical law that, whenever the interchange of the acids of two soluble chem-ical compounds will cause one of the bases to unite with the acid previously combined with the other base, and form an insoluble compound, this reaction always takes place whenever the solutions are brought together, regardless of the chemical affinities of the two bases. As this law explains many chemical phenomena formerly supposed to be rather strange, we think it worth while to direct our readers' attention to it.
There are several other ways of producing the solution of the acetate of copper; but as the salts required are not as cheap as those mentioned, the old process is still preferred. It is not necessary to use the crystallized blue vitriol or the lead-sugar. The pure concentrated solutions may be made from the copper and lead, and used in place of the solutions made from the crystallized salts. There is no difference in the result, whether lead-sugar or acetate of baryta is used, except that in the first case the incidental product is the precipitate of sulphate of lead, a substitute for white-lead, and in the second case, sulphate of baryta, or heavy spar, a substance largely used for adulterating white-lead.
To produce the precipitate in the best manner, the solution of the acetate is slightly heated, placed in the precipitating vessel and constantly stirred, while the solution of sulphate of copper is slowly added. A white precipitate immediately commences to fall down, and the addition of the copper solution is continued as long as it produces any precipitate; consequently it must be added with care toward the end of the operation, in order to avoid an excess of the copper solu-tion. If an excess has been added, a quantity of the acetate solution must be added slowly till this fails to produce a precipitate, so that we may be sure that no excess of either salt is present. In order to test this more fully, a small quantity of the mixture is filtered into a test-glass, and a few drops of either solution added. If a few drops of one produce a cloudiness, we know that we have added too much of the other to the mixture. The intensity of this cloudiness indicates to the experienced workman the amount of the solution which must be added to the mixture to avoid an excess of either salt. When the required correc-tions have been made, the solution is allowed to settle for several hours, so that the supernatant fluid is perfectly clear. This is then drawn off by copper or wooden stop-cocks at the side of the vessel, or by means of siphons. This liquid is then placed in large copper pans, and evaporated at a temperature of 140° to 180° Fahr. As soon as a small portion of the liquid, taken out by: means of a small dipper and cooled, commences to deposit crystals, the fires are withdrawn from under the pans, and strings and sticks are suspended in the liquid. On cooling, crystals of verdigris will deposit themselves upon the sticks and strings as well as on the bottom and sides of the pans.
In the paint manufactories, when the acetate of copper is used for other purposes, the solution is used but not concentrated and crystallized. In this case, the question arises, How much crystallized verdigris is contained in a given quantity, for instance, in ten gallons of the solution? There are, of course, very correct chemical methods of determining this point, but these are not as useful for practical purposes as the following simple method, which is, therefore, universally adopted.
The specific gravity of the solution is ascertained by means of Beaumes hydrometer, and the temperature noted; then a small quantity of pure acetate of cop-per, say one pound, is dissolved in as little water as possible, and then water added till a solution is obtained of the same specific gravity and temperature as the solution, of which the degree of concentration is required. By partially immersing the vessels contain-ing the concentrated solution of the crystals, and the water with which it is to be diluted, in the original solution, the equality of temperature is easily obtained. Suppose now that the pound of acetate of copper has been dissolved in a quart of water, in order to bring it to the sane specific gravity as the ten gallons of solution to be tested, it is clear that both solutions would contain acetate of copper at the rate of four pounds per gallon, or forty pounds in the ten gallons.
Some manufacturers do not make the acetate and copper salts, but buy them in crystallized form. For the benefit of these, it is easy to give, once for all, the relative amount of material required to produce a given quantity of verdigris without excess or loss of either material, or without requiring the trouble of testing whether there is any excess of one or the other of the generating salts. According to the theory of chemical equivalents, a solution of one hundred and twenty-five parts, by weight, of sulphate of copper has to be mixed with a solution of one hundred and ninety of lead-sugar, or one hundred and fifty-four and a half of crystallized acetate of baryta, in order to form a complete decomposition, and time recomposition of, theoretically, exactly one hundred pounds of crystallized verdigris, with a precipitate of two hundred and fifteen pounds of sulphate of lead, or one hundred and seventy-five and a half pounds of sulphate of baryta.
Practically, however, the lead or baryta precipitate carries down with it some of the acetate of copper, and both have therefore a greenish color; there is, there-fore, some loss of acetate of copper. By repeatedly washing the precipitate, it may be purified from the adhering verdigris. In this way the precipitate becomes more valuable, while the water used for the washing, and containing some of the copper compound, may be used for the succeeding solutions, and in this nranner the verdigris may also be saved.
Recently, it has become possible to obtain acetate of soda, in crystals or in solution, in large quantities and at low prices, and this gives occasion to another economical way of making a concentrated solution of acetate of copper. The acetate of soda may be obtained by saturating one hun-dred and forty-four parts of crystallized soda with vinegar, filtering through animal carbon in case it is colored, and concentrating by evaporation. Then one hundred and twenty-five parts of sul-phate of copper are dissolved in the same, and a clear solution will be obtained, in which the soda, the copper, the acetate and sulphuric acid are present, but from which a large quantity of acetate of copper may be obtained by crystallization. The strong tendency of this substance to crystallize being in this case the cause of the combination of the copper with the acetic acid, the sulphate of soda, which is very soluble, and hence does not crystallize so easily, will remain in the solution. This solution may, however, be used for many purposes without crystallization.
Also, if twenty-nine parts of pure quick lime are slacked with water, and dissolved in vinegar, the solution concentrated by evaporation, and mixed with a solution of one hundred and twenty-five parts of sulphate of copper, we obtain a precipitate of sulphate of lime, (plaster of Paris, gypsum,) and a solution of acetate of copper, which may be easily separated from the precipitate by decantation and filtration. However, as the gypsum is slightly soluble in water, (one part gypsum in three hundred of cold water) the solution will contain it in this ratio, and can therefore only be used to produce a color less brilliant than that made from pure verdigris. The great trouble in this case is, that the gypsum is less soluble in warm water than in cold water, and that by heating the solution for crystallization the gypsum is deposited with the crystals of verdigris.
Crystallized acetate of copper is also not very soluble in cold water. Four hundred parts of water will dissolve only one part of the crystals. It is, however, much more soluble in hot water; but if boiled for some time it is decomposed, some of the acetic acid being driven off, and causing the solution to become turbid. A bluish basic salt, that is to say, a compound which contains a double amount of copper oxide, is thrown down. Its production may be avoided by never heat ing the solutions to the boiling-point, but keeping them at a temperature between 140° and 180° Fahr., as mentioned above.
The crystallized acetate of copper is seldom used as a paint, while the basic impure verdigris described in our former number (page 334) is much more adapted for this purpose. It comists of forty per cent of oxide of copper, fifty-one per cent of acetic acid, and nine of water. Its chemical formula is Cu O, (C4H3O3) +HO, which expresses most beautifully this composition according to the definite amount of matter expressed by each symbol. Cu always represents thirty-two parts of copper; O, eight parts of oxygen; C, six parts of carbon; H, one of hydrogen; and for the benefit of students in chemistry, we close this article on the most important of all copper compounds for the ma-nufacture of paints, with a simple calculation of the amount of each ingredient entering in its composition.
It serves at the same time as an illustration of what was commenced to be taught in a former number of The Manufacturer and Builder.
Oxide of Copper, (Cu O) = 32+8 =40
Acetic acid (C4H3O3)=4 x 6+3+3 x 8 =51
Water, (HO)=1+8 = 9
Acetate of copper, Total, 100
9.7.14
8.7.14
Tupakka ja sen käytäntö seurauksineen.
Kylväjä 11, 14.3.1907
(Jatkoa 4:teen n:oon.)
IV. Tupakan waikutus terweyteen.
edellä jo mainittiin, että tupakka waikuttaa myöskin haitallisesti näköön. Myrkytyksen saaneen henkilön näkö heikkenee, ja se woi tapahtua jokseenkin äkkiä. Tarkkojen tutkimusten perästä huomaa lääkäri wian olewan silmähermossa. Useasti tapahtuu myöskin, että tällainen silmäsairas näkee wärejä epätarkasti, hänen "wäriaistinsa" on enemmän tai wähemmän heikontunut, woi olla niinkin, että hän on muutamiin wäreihin nähden aiwan wärisokea. Jos jollakin esineellä on joku noista wäreistä, joiden suhteen henkilö on wärisokea näkee hän esineen kokonaan toisen wärisenä. Jotensakin sama waikutus on toisillakin myrkytyksillä, erittäinkin pitkäaikaisella alkoholin käyttämisellä. Sairas woi olla pelastettawissa, jos hän luopuu näiden aineiden käyttämisestä, mutta jos myrkytystä jatketaan, tulewat seuraukset aina waarallisemmiksi, ne woiwat johtaa täydelliseen sokeuteen. Tämä tulee siitä, että myrkky on auttamattomasti turmellut silmähermossa olelvat hermosäikeet.
Tämän yhteydessä sopii huomauttaa siitä waarasta, mihinkä tupakan, alkoholin y. m. s, aineiden nauttiminen wie henkilön, jonka esiin, rautateillä, merellä y, m. täytyy olla tekemisissä wärillisten merkinantolippujen kanssa. Jokainen tietää, että sellaisilta henkilöiltä waaditaan tarkkaa wärien tuntemista, mutta, jos he tupakan tahi alkoholin käyttämisen kautta owat yhtäkkiä saaneet wäriaistinsa pilalle, woiwat he tietämättään, tahtomattaan olla syynä mitä hirwittämimpiin onnettomuuksiin.
Piirilääkäri Sellden luettelee joukon waikeita tauteja, jotka johtuwat nikotiinimyrkytyksestä. Hän sanoo: "Asiantuntijat laskewat monet waaralliset wammat ja kiwut tupakan käytännön laskuun, niinkuin esim. heikontunut ruoansulatus (tupakoitsijan kalpeat kaswot ja sairaaloinen ihonwäri owat seurauksia turmeltuneesta ruoansulatuksesta), raswoittunut sydän (erittäinkin niillä sikarin polttajilla, jotka nielewät samun), syöpä huulissa, muistin katoaminen, sokeus, mielenwikaisuus ja tylsämielisyys.
Tohtori Ladroid de Charriére huomauttaa, että tupakan poltolla on suurempi syy ja waikutus korwatauteihin kuin yleensä osataan aawistaakaan.
Häiritty sydämen toiminta on yksi warmimmin ja useammin ilmestywä merkki kroonillisesta nikutiinimyrkytyksestä. Waltimo lyö epäsäännöllisesti.
Näistä on seurauksena, että sairasta rupeaa waiwaamaan kiusallinen ikäwän tunne. Häirittyyn sydänten toimintaan liittyy tawallisesti häiriytynyt hengitys.
"Juurtunut tapa polttaa tupakkaa, waikuttaa epäilemättä sangen wahingollisesti werenkierron keskuselinten supistumiseen. Ei kukaan woi tarkastella tupakan suoranaista waikutusta tulematta wakuutetuksi siitä, että sitä ei woi wiedä ihmisruumiiseen ilman, ettei se häiritsewästi waikuta sydämeen ja aikaansaa sen toiminnassa heikkoutta. Se tila, jonka tupakka aikaansaa, kehittyy nopeasti ja kestää useita minuutteja, jopa tuntejakin joka kerta", sanoo tohtori Richardson.
Nikotiinimyrkytys tunkeutuu wereenkin. Siitä sanoo tohtori Richardson seuraawaa: "Tupakansawun sisäänhengitys waikuttaa pikaisen muutoksen punaisissa werisoluissa. Jos niitä katsoo mikroskoopilla, niin huomaa, etta ne owat kadottaneet pyöreän muotonsa ja tulleet soikeiksi, epäsäännöllisiksi ja kulmikkaiksi, ja sisäisen wetowoiman asemesta, joka niillä on toisiinsa nähden - seikka, joka warmojen olettamusten mukaan on hywän terweyden merkki - löydämme ne hajallaan siellä täällä. Niin ne antawat tiedemiesten yhtä selwästi ymmärtää kuin jos ne osaisiwat puhua, että henkilö, jonka werisolut omat sellaisessa tilassa, tuntee itsensä fyysillisesti heikontuneeksi ja niinhywin lihaswoima kuin sielunkin kywyt owat kärsineet wahinkoa."
(Jatkoa 4:teen n:oon.)
IV. Tupakan waikutus terweyteen.
edellä jo mainittiin, että tupakka waikuttaa myöskin haitallisesti näköön. Myrkytyksen saaneen henkilön näkö heikkenee, ja se woi tapahtua jokseenkin äkkiä. Tarkkojen tutkimusten perästä huomaa lääkäri wian olewan silmähermossa. Useasti tapahtuu myöskin, että tällainen silmäsairas näkee wärejä epätarkasti, hänen "wäriaistinsa" on enemmän tai wähemmän heikontunut, woi olla niinkin, että hän on muutamiin wäreihin nähden aiwan wärisokea. Jos jollakin esineellä on joku noista wäreistä, joiden suhteen henkilö on wärisokea näkee hän esineen kokonaan toisen wärisenä. Jotensakin sama waikutus on toisillakin myrkytyksillä, erittäinkin pitkäaikaisella alkoholin käyttämisellä. Sairas woi olla pelastettawissa, jos hän luopuu näiden aineiden käyttämisestä, mutta jos myrkytystä jatketaan, tulewat seuraukset aina waarallisemmiksi, ne woiwat johtaa täydelliseen sokeuteen. Tämä tulee siitä, että myrkky on auttamattomasti turmellut silmähermossa olelvat hermosäikeet.
Tämän yhteydessä sopii huomauttaa siitä waarasta, mihinkä tupakan, alkoholin y. m. s, aineiden nauttiminen wie henkilön, jonka esiin, rautateillä, merellä y, m. täytyy olla tekemisissä wärillisten merkinantolippujen kanssa. Jokainen tietää, että sellaisilta henkilöiltä waaditaan tarkkaa wärien tuntemista, mutta, jos he tupakan tahi alkoholin käyttämisen kautta owat yhtäkkiä saaneet wäriaistinsa pilalle, woiwat he tietämättään, tahtomattaan olla syynä mitä hirwittämimpiin onnettomuuksiin.
Piirilääkäri Sellden luettelee joukon waikeita tauteja, jotka johtuwat nikotiinimyrkytyksestä. Hän sanoo: "Asiantuntijat laskewat monet waaralliset wammat ja kiwut tupakan käytännön laskuun, niinkuin esim. heikontunut ruoansulatus (tupakoitsijan kalpeat kaswot ja sairaaloinen ihonwäri owat seurauksia turmeltuneesta ruoansulatuksesta), raswoittunut sydän (erittäinkin niillä sikarin polttajilla, jotka nielewät samun), syöpä huulissa, muistin katoaminen, sokeus, mielenwikaisuus ja tylsämielisyys.
Tohtori Ladroid de Charriére huomauttaa, että tupakan poltolla on suurempi syy ja waikutus korwatauteihin kuin yleensä osataan aawistaakaan.
Häiritty sydämen toiminta on yksi warmimmin ja useammin ilmestywä merkki kroonillisesta nikutiinimyrkytyksestä. Waltimo lyö epäsäännöllisesti.
Näistä on seurauksena, että sairasta rupeaa waiwaamaan kiusallinen ikäwän tunne. Häirittyyn sydänten toimintaan liittyy tawallisesti häiriytynyt hengitys.
"Juurtunut tapa polttaa tupakkaa, waikuttaa epäilemättä sangen wahingollisesti werenkierron keskuselinten supistumiseen. Ei kukaan woi tarkastella tupakan suoranaista waikutusta tulematta wakuutetuksi siitä, että sitä ei woi wiedä ihmisruumiiseen ilman, ettei se häiritsewästi waikuta sydämeen ja aikaansaa sen toiminnassa heikkoutta. Se tila, jonka tupakka aikaansaa, kehittyy nopeasti ja kestää useita minuutteja, jopa tuntejakin joka kerta", sanoo tohtori Richardson.
Nikotiinimyrkytys tunkeutuu wereenkin. Siitä sanoo tohtori Richardson seuraawaa: "Tupakansawun sisäänhengitys waikuttaa pikaisen muutoksen punaisissa werisoluissa. Jos niitä katsoo mikroskoopilla, niin huomaa, etta ne owat kadottaneet pyöreän muotonsa ja tulleet soikeiksi, epäsäännöllisiksi ja kulmikkaiksi, ja sisäisen wetowoiman asemesta, joka niillä on toisiinsa nähden - seikka, joka warmojen olettamusten mukaan on hywän terweyden merkki - löydämme ne hajallaan siellä täällä. Niin ne antawat tiedemiesten yhtä selwästi ymmärtää kuin jos ne osaisiwat puhua, että henkilö, jonka werisolut omat sellaisessa tilassa, tuntee itsensä fyysillisesti heikontuneeksi ja niinhywin lihaswoima kuin sielunkin kywyt owat kärsineet wahinkoa."
7.7.14
Black Oxide of Manganese.
Scientific American 13, 22.9.1866
Messrs. Editors: - In answer to "E. H. L. of Mo," in last week's Scientific American, we would state that there are mines of oxide of manganese in California, Ohio, Virginia, and near St. John, N. B., from the latter of which large quantities are being constantly shipped to the bleaching powder manufacturers of England, beside being extensively used here in the manufacture of glass, steel, varnish, refining of coal oil, etc. For the manufacture of crystal glass, which requires the best article of manganese, the New Brunswick has been pronounced by New York, Boston, and Pittsburgh manufactures equal to the best Saxon.
Merrit. W. Griswold & Co.
Agents for N. B. Manganese Mines.
New York, Sept. 14, 1866.
Messrs. Editors: - In answer to "E. H. L. of Mo," in last week's Scientific American, we would state that there are mines of oxide of manganese in California, Ohio, Virginia, and near St. John, N. B., from the latter of which large quantities are being constantly shipped to the bleaching powder manufacturers of England, beside being extensively used here in the manufacture of glass, steel, varnish, refining of coal oil, etc. For the manufacture of crystal glass, which requires the best article of manganese, the New Brunswick has been pronounced by New York, Boston, and Pittsburgh manufactures equal to the best Saxon.
Merrit. W. Griswold & Co.
Agents for N. B. Manganese Mines.
New York, Sept. 14, 1866.
6.7.14
Printing of Woven Fabrics.
Scientific American 13, 22.9.1866
Popular appregension usually confines the application of the "art preservative" to the multiplication of books, newspapers, or other periodicals, and the permanence of ideas which, spoken only, would be evanescent and die with their originator or his cotemporaries. But, although the preservation of ideas belongs mainly to that adaption of printing which gives to writing its lease of life, by indefinite multiplication of copies, an idea may be as surely protected, it it appeals to the fancy and innate love of beauty, as though it confined its appeal to the intellect exclusively.
Printing is truly the "art of arts." It reproduces indefinitely the theories, ideas, and practical facts of thinkers and workers, and it as well subserves the purpose of him whose object is to appeal to the fancies and tastes of all classes. The production of figures oncloths is as really printing as the preservation of ideas by means of the letter type. The decoration of plain cloths with figures is one of the olders of arts. It was practiced by the ancients, and the Chinese and Aztecs were in possession of the art when they became first known to Europeans. To this day the Chinese use the same method in printing cloths that the ydo in printing books. In the latter case we have improved upon their process in using movable types. instead of engraving on and printing from the blocks - we using in our stereptype process the movable types to produce the block, whereas they engrave the block itself. In the former case it is but a few years since machine printing took the place of hand block prining in figuring calicoes.
This method of producing colored figures on cloths by means of prinitng, should not be confounded with dyeing, although by a previous protection of those portions of the fabric not intended to be colored, dyeing has been employed to make figured cloths. Printing deposits the colors directly upon the cloth, which are secured there by mordants. This art, brought from the East, found its way into England about the year 1676. We will briefly describe the process formerly used.
"Block printing" of calicoes was comparatively a simple process. The web of white cloth was sent to the printing shop, either in a bleached state, or dyed some color which formed the ground. Previous to being submitted to the manipulations of the printer it was "calendered," or pressed between heavy rollers, which gave it a perfect surface. It was then ready for the printer. He worked at a table, wide enough to accommodate the fabric, and six or seven feet long. The roll of plain cloth lay at one end of the table on a platform, and was drawn up over the table, which was of stone and covered with a thick felt blanket. Behind him was a tub, some thirty or thirty-six inches diameter, partially filled with a mixture of common pitch and a vehicle which held it in solution. Floating on the surface of this yielding mass was a piece of woolen cloth stretched tightly over a hoop. A pot of the requisite color stood at the side, and the attendant, or "tearer," as eh was called, with a flat brush smeared the hooped woolen sieve with the color. The printer was furnished with a "block," corresponding in length and width with the pattern to be printed, the face of which was cut in relief, as are the blocks used now in prining wood cuts. By dipping lightly the block in the sieve, floating on the yielding surface, it took up enough of the color to make an impression on the cloth. The cloth being drawn tightly over the table presented a smooth surface, upon which, by repeated applications of the block, its pattern was produced and reproduced indefinitely, the "tearer" smearing the sieve with fresh color in each interval. The printer was guided in placing his block by a minute pin inserted at a corner of his block. The cloth on the surface of the table being printed, it was wound up over rollers traversing the room on racks, so that when it came back byt the series of rollers to the end of the table, it was wound perfectly dry upon a shaft, from which it was taken to be "lived" or "raised".
This is, in brief, the modus operandi of block printing in its simplest form. It will be seen that several applications of the block were required to cover one single transverse section of the fabric, and many repeated applications to print a full web of thirty or forty yards in length. Sometimes the ground itself was applied by blocks. In such a case the figure was first printed with the block cut in relief, and then the fabric was reprinted with a block cut in intaglio, the figure being sunk into its surface, and the surface itself being faced with woolen or felt, to convey a large portion of the coloring matter. Another style was that of printing several colors or shades at once by means of an apparatus which fed different colors at the same time. Technically this was termed a "hokey-pokey" tub. The deposition of the colors, held in reservoirs, was effected by the pressure of the block, in dipping, acting upon compressed air.
This block printing is still employed in the prining of silk handkerchiefs, each one of which is a single pattern, and largely in the prining of floor and table oil cloths. In the latter case the coloring matter is not a dye, but a paint, and is deposited mainly on the surface of the fabric.
Machine printing by means of engraved copper rollers, has now taken the place of block prinitng, and that we shall make a subject for another article. When machine printing was first practiced in England and France, he colors used were not deemed "fast," and much prejudice was excited against the product of the new process. Hand-printed calicoes were eagerly sought after, and as the process of hand printing could not be so accurate as that done my machinery, those who studied economy rather than show, sought eagerly, in their selection of calicoes, for evidences of faults to make sure that they were getting the genuine article. The shrewd suppliers of our markets abroad soon ascertained the fact, and sent to this country imperfectly-printed goods, printed by machinery, to suit the queerly-fastidious tastes of the purchasers in the American market. Labor-saving machinery, however, ultimately triumphed over old and slow processes, and the days of block printing were numbered.
Popular appregension usually confines the application of the "art preservative" to the multiplication of books, newspapers, or other periodicals, and the permanence of ideas which, spoken only, would be evanescent and die with their originator or his cotemporaries. But, although the preservation of ideas belongs mainly to that adaption of printing which gives to writing its lease of life, by indefinite multiplication of copies, an idea may be as surely protected, it it appeals to the fancy and innate love of beauty, as though it confined its appeal to the intellect exclusively.
Printing is truly the "art of arts." It reproduces indefinitely the theories, ideas, and practical facts of thinkers and workers, and it as well subserves the purpose of him whose object is to appeal to the fancies and tastes of all classes. The production of figures oncloths is as really printing as the preservation of ideas by means of the letter type. The decoration of plain cloths with figures is one of the olders of arts. It was practiced by the ancients, and the Chinese and Aztecs were in possession of the art when they became first known to Europeans. To this day the Chinese use the same method in printing cloths that the ydo in printing books. In the latter case we have improved upon their process in using movable types. instead of engraving on and printing from the blocks - we using in our stereptype process the movable types to produce the block, whereas they engrave the block itself. In the former case it is but a few years since machine printing took the place of hand block prining in figuring calicoes.
This method of producing colored figures on cloths by means of prinitng, should not be confounded with dyeing, although by a previous protection of those portions of the fabric not intended to be colored, dyeing has been employed to make figured cloths. Printing deposits the colors directly upon the cloth, which are secured there by mordants. This art, brought from the East, found its way into England about the year 1676. We will briefly describe the process formerly used.
"Block printing" of calicoes was comparatively a simple process. The web of white cloth was sent to the printing shop, either in a bleached state, or dyed some color which formed the ground. Previous to being submitted to the manipulations of the printer it was "calendered," or pressed between heavy rollers, which gave it a perfect surface. It was then ready for the printer. He worked at a table, wide enough to accommodate the fabric, and six or seven feet long. The roll of plain cloth lay at one end of the table on a platform, and was drawn up over the table, which was of stone and covered with a thick felt blanket. Behind him was a tub, some thirty or thirty-six inches diameter, partially filled with a mixture of common pitch and a vehicle which held it in solution. Floating on the surface of this yielding mass was a piece of woolen cloth stretched tightly over a hoop. A pot of the requisite color stood at the side, and the attendant, or "tearer," as eh was called, with a flat brush smeared the hooped woolen sieve with the color. The printer was furnished with a "block," corresponding in length and width with the pattern to be printed, the face of which was cut in relief, as are the blocks used now in prining wood cuts. By dipping lightly the block in the sieve, floating on the yielding surface, it took up enough of the color to make an impression on the cloth. The cloth being drawn tightly over the table presented a smooth surface, upon which, by repeated applications of the block, its pattern was produced and reproduced indefinitely, the "tearer" smearing the sieve with fresh color in each interval. The printer was guided in placing his block by a minute pin inserted at a corner of his block. The cloth on the surface of the table being printed, it was wound up over rollers traversing the room on racks, so that when it came back byt the series of rollers to the end of the table, it was wound perfectly dry upon a shaft, from which it was taken to be "lived" or "raised".
This is, in brief, the modus operandi of block printing in its simplest form. It will be seen that several applications of the block were required to cover one single transverse section of the fabric, and many repeated applications to print a full web of thirty or forty yards in length. Sometimes the ground itself was applied by blocks. In such a case the figure was first printed with the block cut in relief, and then the fabric was reprinted with a block cut in intaglio, the figure being sunk into its surface, and the surface itself being faced with woolen or felt, to convey a large portion of the coloring matter. Another style was that of printing several colors or shades at once by means of an apparatus which fed different colors at the same time. Technically this was termed a "hokey-pokey" tub. The deposition of the colors, held in reservoirs, was effected by the pressure of the block, in dipping, acting upon compressed air.
This block printing is still employed in the prining of silk handkerchiefs, each one of which is a single pattern, and largely in the prining of floor and table oil cloths. In the latter case the coloring matter is not a dye, but a paint, and is deposited mainly on the surface of the fabric.
Machine printing by means of engraved copper rollers, has now taken the place of block prinitng, and that we shall make a subject for another article. When machine printing was first practiced in England and France, he colors used were not deemed "fast," and much prejudice was excited against the product of the new process. Hand-printed calicoes were eagerly sought after, and as the process of hand printing could not be so accurate as that done my machinery, those who studied economy rather than show, sought eagerly, in their selection of calicoes, for evidences of faults to make sure that they were getting the genuine article. The shrewd suppliers of our markets abroad soon ascertained the fact, and sent to this country imperfectly-printed goods, printed by machinery, to suit the queerly-fastidious tastes of the purchasers in the American market. Labor-saving machinery, however, ultimately triumphed over old and slow processes, and the days of block printing were numbered.