Scientific Notices. On the coloring matter of the orange-leaved Morinda (Morinda citrifolia.)

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

By Mr. T. Anderson.

The substance which forms the subject of this paper was introduced some time ago into Glasgow under the name of Sooranjee, as a substitute for madder in the operation of dyeing. Experiments were, immediately after its importation, made with it by some of the first cotton printers in Glasgow, and the uniform opinion formed was, that this substance was not a coloring matter, and, therefore, could not be of any utility. Professor Balfour having forwarded some samples of the root to Mr. Anderson, that gentleman subjected them to chemical analysis. The seeds of this plant seemed perfectly identical with those of the sooranjee or soorinjee,—a quantity of which Mr. Anderson had formerly received from Bombay. This plant appears to have been long known and employed by the natives for the production of coloring matter. Unfortunately Mr. Anderson did not succeed in causing these seeds to germinate, which prevented the possibility of his studying the native plant itself, and comparing its characteristics with those of the pretended mother plant.

The morinda citrifolia has been described by Rheede (Hortus Malabaricus I., 97) under the name of cada pilava and is known to botanists under the name of Bancutus latifolia Rumphi (Herbar Amboinense V., cap. 13). In these works, it is expressly stated that the roots of the species mentioned do not possess any dyeing properties; whilst those of the Bancutus angustifolia, or morinda citrifolia, of modern botanists (doubtless the wongkudu of the Japanese dyers) is employed for the production of a splendid scarlet color. An exact description of the cultivation of the morinda citrifolia, and its employment for dyeing, is given by Hunter (Asiatic Researches IV., 35). He also calls attention to the fact, that this plant is known in Malacca under the name of aal, and in Oude under that of atchy. It does not appear that any chemical analyses have yet been made of this root. Dr. Bancroft has, however, made some observations upon a root introduced from India under the name of aurtch, which resembles madder in appearance, and seems to belong to the morinda citrifolia. As to the name sooranjee, which it has received, no definite information could be arrived at as to its derivation. Sooranjee is the root of the plant; and, as imported, it consists of pieces from one to two inches in thickness, and varying in diameter from three to twelve-thirtieths of an inch. In the largest pieces, the bark is thick, and constitutes the greatest part of the root; but, in pieces of a smaller size, the bark is much thinner,—its outside color is of a pale yellowish-brown; but, when broken, it presents, in the interior, a color varying from a fine yellow to a reddish-brown. The wood itself is of a light yellow color, becoming deeper towards the centre, and scarcely perceptible near the bark. Alkalies cause it to assume a deep red color, which indicates the presence of a certain quantity of coloring matter. The bark or rind is easily removed, and presents, on its inner face, a peculiar silvery lustre, which is very evident in large pieces, but is scarcely discernible in the small pieces. On boiling in water, the inside furnishes a yellow color; and, if boiled with alcohol, a deep red is produced.

In order to prepare the coloring matter from sooranjee, which Mr. Anderson calls morindin, the treatment with boiling water was first adopted, —preliminary experiments having shewn that this substance was easily soluble in that liquid: it was soon as certained, however, that this method was not applicable, as the decoction contained a viscous matter, which presented an obstacle to filtration. The employment of alkalies, in which this substance is rapidly dissolved, appeared also to be impracticable; Mr. An derson was therefore obliged to have recourse to alcohol, which perfectly answered the purpose. The bark or rind, after being deprived of all its ligneous parts, and ground to a fine powder, was boiled with six times its weight of rectified alcohol. The solution, after having been filtered while hot, was of a deep brownish-red color; and, on cooling, deposited a brown flaky precipitate, containing the morindin, and other coloring matters found in the root, although in small proportion. A second decoction, with the same quantity of alcohol, furnished a paler solution, in which the morindin was deposited with a much less quantity of red coloring matter. The same treatment was repeated until, on the dyeing matter cooling, no further deposit was obtained. Each of these latter decoctions furnished a substance purer and purer,—so that, at last, it was deposited in the form of small yellow crystals. By means of repeated crystalliza tion in alcohol at 50°, the red substance was completely removed and a fine yellow color obtained; but still some impurity remained,—for, in one instance, a residuum of 0.47 per cent. of ash was left; and, in another, a residuum of 0.32 per cent. The elimination of these mineral matters could not be effected by crystallization in alcohol, but only in alcoholic solutions, sharpened with hydrochloric acid. In this liquor the morindin is crystallized in a perfectly pure state.

Morindin is separated from its solution in the form of small crystals, grouped in the same manner as those of the wavelite. These crystals are exceedingly delicate, and, when collected and dried on a filter, present the appearance of a sulphur-colored mass, having a silky lustre. These crystals are not very soluble in cold alcohol; but are dissolved, in large proportion, in boiling alcohol, especially when it is diluted. The solution, on cooling, is converted into a mass of crystals, which shrink very much on being dried, are but slightly soluble in alcohol, and almost in soluble in ether.

Morindin is dissolved, in very small proportion, by means of cold water; but sufficient to impart a yellow color to it. At the boiling point, it is dissolved in much greater abundance; and, on cooling, is precipitated from its solution in the form of a gelatinous mass, which presents no traces of crystallization. It obstructs the passages of the filter, and, consequently, cannot be separated from its mother liquor. Morindin is dissolved by alkalies, which impart to it a fine orange-red color. By concentrated sulphuric acid it is changed to a deep purple-red, which, in thin layers, appears of a violet color. After remaining in a state of repose for twenty-four hours, the solution, on being diluted, deposits yellow flakes of coloring matter, completely insoluble in cold water, and furnishing, with ammonia, a violet and not an orange-colored solution. Nitric acid, of sp. gr. 1-28, in the cold state, slowly dissolves morindin, and is thereby converted into a deep brownish-red color. In the hot state, the action is brisk, the brown color disappears, and nitrous vapours are disengaged in abundance. The liquor, on being submitted to continued ebullition, and neutralized by means of ammonia, furnished no precipitate with salts of lime.

Morindin in solution gives, with basic acetate of lead, a crimson-red precipitate, flaky, and extremely fugitive, and which cannot be washed without loss of coloring matter. Solutions of baryta, strontian, and lime, furnish an abundant red precipitate, slightly soluble in water. Chloride of iron produces a deep brown color, but does not give any precipitate. On adding alum to an ammoniacal solution of morindin, this latter is precipitated, together with the alumina, in the form of reddish-colored lac; and by the addition of chloride of iron, the precipitate becomes brown, and is not distinguishable from that of pure oxide of iron; it however contains the whole of the morindin,—the supernatant liquor being colorless. On heating the morindin in a close vessel, it melts into a deep brown liquid, which boils at a high temperature, and afterwards disengages vapors of a splendid orange-color, analogous to the nitrous vapors, and which are deposited upon cold bodies in the form of oblong red crystals;—a large quantity of carbonaceous residuum remaining in the vessel. An elementary analysis of morindin gave results which agree with the formula C28H15O15. From this formula it would appear, that a remarkable analogy exists between morindin and the coloring matter of madder. This circumstance is so much the more worthy of notice, that it indicates identity in the chemical nature of plants, which approach very nearly to each other in natural classification. Morinda, in fact, belongs to the natural family of chicoraceoe, which is considered by many botanists to be a subdivision of the rubiacece, of which madder (rubia tinctorum is the type. This analogy does not extend further than the coloring properties,—the two substances differing essentially from each other.

It has been stated above, that the experiments of several printers at Glasgow, to produce upon cotton fabrics a coloring matter from sooranjee, completely failed. This is quite confirmed as respects the ordinary methods of mordanting. Mr. Anderson digested some morindin for a considerable time, and at a gradually increasing temperature, with pieces of stuff which had been mordanted with alumina and iron; the coloring matter was not, however, fixed, and the mordants, after boiling for a few minutes with soap, did not undergo any alteration. With the root itself, the fabric, mordanted with alum, acquired a greyish-red color, and with iron a rather deeper color; there was, however, considerable difference on trying a fabric mordanted for dyeing Turkey-red.

Mr. Anderson procured from Glasgow specimens of cotton fabric, prepared for Turkey-red according to the old and also the new method, and found, that after the lapse of a few hours, both of them had acquired a deep red-brown color, which did not possess any beauty, but was perfectly fast. These observations agree with the remarks made by Hunter on the method employed by the Hindoos in dyeing with the morinda plant. According to his account, the fabric is first immersed in an imperfect soap, obtained by mixing oil of sesame with soda lye, and, after being washed and scoured, it is treated with a decoction of myrobolans (astringent fruits of the Terminalia chebula) and finally exposed, for four or five days, to the sun. After undergoing this treatment, it is immersed in an alum bath; it is then wrung dry and again exposed for four or five days.

By another method the morinda roots are pulverized, damped with sesame oil, and mixed with the flowers of the Lythrum fruticosum, or a corresponding quantity of Purwas (galls of a species of mimosa). This mixture is, with the cotton, introduced into a large quantity of water, and kept at the boiling point over a moderate fire for about three hours: a red color is thus obtained, which, according to Hunter, possesses great durability and beauty. This process is the one usually employed for dyeing Turkey-red; but Hunter further states, that with fabrics mordanted with iron a fixed purple-red or a chocolate color may be obtained; and that in that case the color is probably produced by the tannic acid of the astringent substance employed in the process.

It has been stated above, that morindin is decomposed by heat, and a carbonaceous residuum left in the vessel,—a crystallizable matter, totally different in its properties from the original substance, being sublimed. Mr. Anderson gives to this substance the name of morindon. It has the form of long crystals, which, when inspected through a microscope, present the appearance of six-sided prisms, with an oblique base, and have a red color of extraordinary brightness. These crystals are insoluble in water (either hot or cold), but will readily dissolve in either alcohol or ether. The morindon may be easily obtained from these solutions, in the form of crystals, by careful evaporation. This substance is dissolved by alkalies, and thereby acquires a rich violet color. Concentrated sulphuric acid also dissolves it, and imparts to it the same rich violet color: on evaporating the solution a precipitate is formed. By adding alum to an ammoniacal solution, a red lac is produced; and with barytawater a cobalt blue precipitate is formed. The small quantity of morindon obtained did not allow of its being brought to a perfect state of purity; Mr. Anderson, therefore, merely washed the sublimed crystals with ether, in order to deprive them of all empyreumatical matters, and dried them at the temperature of 100° Cent. On analysis they furnished a result agreeing with the formula C^H^Oi0. Morindon, therefore, appears to be produced from morindin by the elimination of water; and this is confirmed by the change morindin undergoes when brought into contact with sulphuric acid. As was above stated, morindin is insoluble in water, and furnishes, with alkalies, a violet color: this is also the case with morindon. Now, as the sulphuric acid acts in the ordinary manner, viz., by extracting the water, it appears very likely that the morindin loses five equivalents of water, and is thereby converted into morindon.

Supposing that further experiments should confirm the for mula given above for morindon, a strong analogy would be established between the coloring matter of this suhstance and that of madder,—the only difference between them being that of one equivalent of water. It appears, therefore, that morindon really is a coloring matter, and is capable of entering into combination with the ordinary mordants. With alumina it furnishes a deep lively red, and with iron a violet or black. These colors are, however, not fast, and moreover have the disadvantage of combining with the non-mordanted portions of the fabric, and of adhering to the parts desired to be left white. The morindon, when treated with sulphuric acid, will enter into combination with the ordinary mordants.

The discovery of a peculiar coloring matter, which only combines with a fabric which has been treated with oil, in the manner practised for Turkey-red dyeing, is so much the more interesting that it shews the existence of a peculiar class of substances which had not hitherto been noticed. The theory of Turkey-red dyeing, which has been for many years a secret in chemistry, may, perhaps, by this means, have some light thrown upon it; for, although this method of dyeing was imported into Europe some centuries ago, and many improvements have been made upon it, yet, during this lengthened period, no satisfactory explanation of the process has yet been arrived at.

It may be presumed, that by the action of the dung, which is employed in large quantity, the fabric becomes, as it were, animalized; by means of which it acquires the property of being charged with finer and brighter colors than when simply mordanted with mineral substances. Further researches have moreover proved, that the oil, which is employed in large quantity in Turkey-red dyeing, when brought into contact with the air and with decomposed animal matter, becomes also decomposed, and is converted into a sort of resinous matter, which constitutes the mordant for Turkey-red dyeing. M. Weissgerber, to whom we are indebted for some experiments on this subject (an account of which is given by M. Persoz in his Traité Théorique et Pratique de l'impression des Tissus, Vol. III., p. 174), found that fabrics treated with oil took a fine lively red; that, by means of acetone, the oil might be extracted, and that it would be found to have undergone no change; also, that after each successive application of the acetone, the fabric gradually lost the property of taking up the coloring matter of the madder, until at last (the whole of the oil having been extracted) the fabric would come out of the dyebath without taking up any color. The same chemist also found, that by employing the extract obtained by the acetone, as a mordant, a very fine color was produced with madder, without the necessity of adding any other substance. The observations of M. Weissgerber are confirmed by the experiments detailed in this memoir; there being no doubt that the deep red color obtained from morindin was produced in a manner totally independent of the alum, as this salt does not possess the property of fixing the coloring matter.

M. Persoz and Mr. Anderson both seem to be of opinion that the alum now used for Turkey-red dyeing will be completely abandoned, when Turkey-red dyers shall have become acquainted with the nature of the modification which the oil undergoes during the operation.

Recipes for Colored Potters' Glazings.

Scientific American 5.6.1869

White Glazing. - Prepare an intimate mixture of four parts of massicot, two parts of tin ashes, three fragments of crystal glass, and one-half part of sea salt. The mixture is suffered to melt in earthen-ware vessels, when the liquid flux may be made use of.

Yellow Glazing. - Take wqual parts of massicot, red lead, and sulphuret of antimony. Calcine the mixture and reduce it again to powder, add then two parts of pure sand, and one and a-half parts of salt. Melt the whole.

Green Glazing. - Two parts of sand, three parts massicot, one part of salt and copper scales, according to the shade to be produced. The mixture is melted as directed above.

Violet Glazing. - One part of massict, three parts of sand one of smalt, and one-eight part of black oxide of manganese.

Blue Glazing. - White sand and massicot, equal parts, one-third part of blue smalt.

Black Glazing. - Two parts of black oxide of manganese, one of smalt, one and a-half of burned quartz, and one and a-half of massicot.

Brown Glazing. - One part of fragments of green bottle glass, one of manganese, and two parts of lead glass.


Recent Patents. To Samuel Brown Oliver [...] for certain improvements in dyeing and dyeing materials

Recent Patents. To Samuel Brown Oliver, of Woodford, in the county of Essex, Gent., for certain improvements in dyeing and dyeing materials,—being a communication.— [Sealed 10th November, 1849.]

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

This invention consists in manufacturing mixtures of the following materials, to be used in dyeing woollen fabrics, or fabrics containing a mixture of wool, viz.: — Sulphuric, nitric, boracic, acetic, arsenious, pyroligneous, oxalic, and tartaric acids—chloride of sodium or common salt—sal-ammoniac— chloride of magnesium—chloride of potassium—sulphate of potash—sulphate of magnesia—sulphate of soda—oxalate of potash—acetate of potash—acetate of soda—nitrate of soda— nitrate of potash—sulphate of zinc — and borax.

The patentee describes seven mixtures, which are those that he prefers to use; but he does not confine himself thereto, as variations in the proportions or substitutions of certain of the materials above enumerated may be made. The first mixture consists of 100 parts of chloride of sodium, 300 parts of water, 10 parts of sulphuric acid, 3 parts of nitric acid, and 1 part of arsenious acid. The second mixture consists of 100 parts of sulphate of soda or sulphate of potash, 6 parts of sulphuric acid, and 2 parts of nitric acid. The third mixture consists of 100 parts of sulphate of soda or potash, 1 part of sulphuric acid, 3 parts of nitric acid, and 6 parts of vinegar (or, instead of the latter, 2 parts of purified acetic acid may be used). The fourth mixture is composed of 100 parts of sulphate of soda or potash, 6 parts of sulphuric acid, and 3 parts of tartaric acid in a state of powder. The fifth mixture consists of 100 parts of nitrate of potash, 30, 40, 50, or 60 parts of sulphuric acid (according to the shade required), and 1000 parts of sulphate of soda or potash. The sixth mixture is composed of 100 parts of the fifth mixture, 3 parts of tartaric acid in a state of powder, and 10 parts of acetate of potash. The seventh mixture consists of 100 parts of sulphate of soda or potash, 4 parts of nitric acid, 4 parts of acetic acid, and 10 parts of tartaric acid in a state of powder.

The first and second mixtures are not to be employed for grain colors, or for any other colors in which solutions of tin are present; but the other mixtures may be employed for all colors,—including grain colors, or other colors in which solutions of tin are present. The materials of which the mixtures are composed are to be left in contact for several days. The vessels in which the above mixtures, or other analogous compounds, are prepared, must be formed of such substances as will not be liable to be acted on by the materials that are to compose the mixture; and which materials are allowed to act on each other until decomposition and admixture are thoroughly effected. The mixtures may be dried by natural or artificial means, and reduced to a state of powder in a mortar or mill.

The mixtures, above described, are to be used in dyeing woollen fabrics, or fabrics in which a mixture of wool is present, in the same manner as cream of tartar or argol is commonly employed,—the same weight of the respective mixtures being taken as would have been taken of cream of tartar or argol. The mixtures are to be employed with the aluminous or other mordants in the ordinary operations of dyeing. For dyeing dark colors, the mixtures may be used without the addition of other mordants; but, for ordinary purposes, they are employed as substitutes for cream of tartar or argol. In conclusion, the patentee says that, having described the invention and stated what he considers to be the best materials for the purposes above mentioned, he wishes it to be understood that he does not claim the use of the acids or salts above enumerated, when taken separately; but he does claim, as the improvements in dyeing and dyeing materials communicated to him, the use of such acids and salts, when combined in the manner and for the purposes above described, or when any of them are made to substitute one another in such mixtures for like purposes. — [Inrolled May, 1850.]


Recent Patents. To James Nasmyth [...] for certain improvements in the method of, and apparatus for, communicating and regulating the power for driving or working machines employed in manufacturing, dyeing, printing, and finishing textile fabrics.

Recent Patents. To James Nasmyth, of Patricroft, near Manchester, in the county of Lancaster, engineer, for certain improvements in the method of, and apparatus for, communicating and regulating the power for driving or working machines employed in manufacturing, dyeing, printing, and finishing textile fabrics.— [Sealed 26th June, 1849.]

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

These improvements apply principally to machines employed in textile manufactures, and consist in communicating the power requisite for driving each separate machine, or system of machines of the same character or description, by means of a separate and distinct steam-engine, placed in direct and immediate connection therewith; and in so arranging the lever connected with the cock or valve which regulates the supply of steam to the said engine, as to enable the attendant work man to communicate, regulate, and disconnect the power which drives the particular machine or system of machines under his superintendence at the time he is inspecting the operation of the machines.

In order that the nature and object of his invention may be clearly understood, the patentee remarks, that, in the management of the several machines employed in the various processes connected with textile manufactures, it is very desirable that the workman should, at all times, have direct and immediate control over the power which drives the machine or system of machines under his charge; in order that he may be able, at any instant, to set in motion or disconnect the said machine or set of machines, without in any way interfer ing with the operations of the machinery adjacent; and also that he may be enabled to regulate the speed of the said machine or system of machines, from the greatest desirable amount of velocity to the slowest degree of motion he may require, whilst the said machines are in motion. These objects have hitherto been but partially attained by certain arrange ments and modifications of connecting and disconnecting apparatus, catch or clutch-boxes, &c., which communicate the motion to the several machines from the system of shafting through which the power of the steam-engine is transmitted; but, by the present method of communicating power, the most direct and perfect control is given to each workman over the power which drives the machine or system of machines under his care. This object is effected by simply placing the handle or lever of the cock or valve of the steam-engine so near to the machine which it drives that the attendant, while watch ing the progress of the operation under his charge, can, at any instant, arrest or modify the velocity of the machine or set of machines under his superintendence.

Another object to be attained by the present invention is, that any particular machine or system of machines may be driven separately, without the necessity of working a large steam-engine, with its train of heavy shafting, gearing, &c.; and also that any number of machines may be connected to, or disconnected from, the driving power, without the liability of breakage or disarrangement (caused by the shock or jerk), which exists, under the present system, when heavy machinery is thrown in or out of gear with the driving power. The patentee suggests that, in the process of dyeing, printing, and many other operations wherein a large quantity of steam is required for heating, drying, and other purposes, the steam should be used at a high pressure for driving the engines, and subsequently passed off to the other processes for which it is required at a lower pressure.

The great importance of the objects to be attained by the improved method of communicating and regulating the power for driving such machinery will, it is said, be at once evident to the practical manufacturer, and may be well exemplified as applied to the machines for printing calico and other similar surfaces, more especially those wherein several colors, forming one pattern, are printed by the machine at one and the same operation; in which, according to the peculiar nature of the work they are intended to perform, it is necessary to adjust and regulate the several parts of the said machine with the greatest accuracy and delicacy previous to commenc ing the process of printing; and as the accuracy of the said adjustments is liable to be deranged (especially when such machines are actuated, as heretofore, by means of gearing, which is common to several adjacent machines), it is requisite for the attendant workman to arrest the progress of the machine, in order that he may be enabled to ascertain whether or not the operation is proceeding in a satisfactory manner. In the ordinary method of communicating the power to such machines, by means of clutch-boxes and other similar contrivances, the connecting and disconnecting of the machines is invariably accompanied, more or less, by a shock or jerk, which is sometimes found to have the effect of disturbing the accurate correspondence of the several parts of the pattern, thereby occasioning what is technically termed a "mis-fit," and frequently, if unobserved, spoiling the piece of goods.

By means of the present invention, it is stated, the attendant workman, having, at starting, accurately adjusted the several parts of his machinery, can cause the machinery to commence working in the most gradual and delicate manner, and keep it so moving that he may not only be enabled to examine the accuracy of the process whilst the machine is in actual motion, but also, by reason of the extreme command which he possesses over the velocity of his machine, he may perform the most delicate adjustments of the several parts without totally arrest ing the progress of the machine. As soon as he finds all the parts in a satisfactory condition and fit state of adjustment, he may gradually increase the speed of his engine to the utmost desirable velocity; and again, when necessary, reduce the same, in order to examine whether the operation is proceeding in a satisfactory manner; and so proceed again, with out actually stopping the machine: the effect of which will be that the piece need not be spoiled, as it is now very liable to be; but the work in question may be performed in a more perfect and satisfactory manner, and in a much shorter time than it has hitherto been effected.

In Plate XVI., the invention is shewn as adapted to some of the machines used in textile manufactures. In all the figures the handle or lever by which the workman controls and regulates the supply of steam to the engine is indicated by a, a. Fig. 1, represents the application of the invention to a calendering machine; fig. 2, shews the same as applied to a mangle; fig. 3, shews the adaptation of the invention to a "padding machine;" and fig. 4, represents the application of the same to a four-color calico printing machine.

The patentee, in conclusion, states that he does not claim, as his invention, any peculiar construction, form, or arrange ment of steam-engine, as adapted to the purposes aforesaid; but he claims the improved method of communicating and regulating the power for driving or working machines employed in manufacturing, dyeing, printing, and finishing tex tile fabrics, by placing a separate and distinct steam-engine in direct and immediate connection with each machine or system of machines; and so arranging the handle of the steam-valve or cock that the attendant workman may, at all times, have perfect control over the engine whilst he is watch ing or inspecting the operation of the machine or system of machines under his charge. — [Inrolled December, 1849.]


Recent Patents. To Andrew Crosse [...] for improvements in tanning hides and skins, and also in dyeing fabrics and substances.

Recent Patents. To Andrew Crosse, of Gloucester-place, New-road, in the county of Middlesex, Gent., for improvements in tanning hides and skins, and also in dyeing fabrics and substances.*— [Sealed 24th May, 1849.]

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850



* The patentee has, by means of a disclaimer, struck out the words "and also in dyeing fabrics and substances" from the title of his patent.
The first part of this invention consists in the application of hydrosulphuret of lime in the process of unhairing hides and skins, by causing the hides and skins to be moistened with and soaked in hydrosulphuret of lime (which is obtained by passing sulphuretted hydrogen through a mixture of lime and water), whereby the hair will be quickly loosened, and may then be removed in the ordinary manner.

The second part of the invention consists in a mode of obtaining strong tannin or other matter from bark, or other substance used in tanning or manufacturing hides and skins into leather. The pulverized or ground bark, or other substance, is first permitted to absorb so much water as may serve to dissolve or set loose the tannin principle or other matter held within the bark or other substance; and then it is subjected to powerful pressure, by means of an hydraulic press or other suitable mechanical apparatus, which causes it to emit an ooze or tanning liquid of a strong kind, i. e., with out so great an admixture of water as may be found in tanning liquid produced by the ordinary method of immersing and soaking the bark or other substance in pits. The improved process is to be repeated upon the same bark or other substance until it no longer contains any tannin or useful matter.

The third part of the invention consists in obtaining electric or galvanic effects in the pits or vessels in which hides and skins undergo the process of tanning. On one side of the pit or vessel is placed a plate of lead, and on the other side a plate of zinc (the plates covering the sides of the pit or vessel); and the two plates are connected together at the upper parts of the same, above the tanning liquid, by means of a strap of either of those metals. The hides or skins, after being unhaired, are suspended in the pit or vessel, which is to be filled with water; the water is allowed to remain therein for three or four days, and then it is either to be removed or else converted into tanning liquor by the addition of bark or other suitable matter; or, the water having been removed, the pit is to be filled with tanning liquor, which is to be kept at the strength of about fifteen degrees of a saccharometer for the first week, and after that the strength is to be increased at the rate of six degrees per week, until a strength of about forty-six degrees is indicated, which is to be maintained until the completion of the tanning process. The patentee says that he does not confine himself to the strengths of the tanning liquor, nor the progressive increase of the strengths above mentioned; and he states that the means of obtaining the requisite electric or galvanic effects in the pit or vessel may be varied.

The patentee claims, as his improvements in tanning hides and skins, Firstly,—the subjecting hides or skins to the action of hydrosulphuret of lime. Secondly,—the improved mode of producing tanning liquid. Thirdly,—the employ ment of means to obtain electric or galvanic effects in the pits or vessels in which hides or skins are under process of tanning.— [Inrolled November, 1849.]


Scientific Notices. On a new method of Gilding Porcelain.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

By M. Grenon.

M. Grenon, decorator of porcelain, of Rue de Faubourg, St. Martin, Paris, submitted to the Society for the Encouragement of National Industry, Paris, an improvement in gilding porcelain, which adds much to its durability.

The operation of gilding, as generally practised, consists, as is well known, in mixing with the preparation of gold and protonitrate of mercury, a certain quantity of subnitrate of bismuth which serves as a flux, and allows the metal to be burnt into the porcelain. The gold prepared by nitrate of mercury, may be applied in extremely thin layers, so that this process will be very economical; it is, however, not very durable. Gold, obtained by sulphate of protoxide of iron, furnishes a more solid, although less economic gilding. Different processes have been employed for rendering gilding more durable without increasing the expense.

M. Rousseau's method is, first to lay a coating of platina, mixed with flux, and then a thin coating of gold upon the platina. This gives a solid gilding, but it is apt to lose its lustre by use,— the color of the gold being modified by that of the platina, which appears when the gold wears away.

M. Grenon's process consists in the successive application of two layers of gold, each having a special flux, and in different proportions. The first layer is first burnt in at a high tempera ture; after which, it is polished with rotten-stone, and on it is laid a thin coating of mercury-gold, which is prepared and burnt in the ordinary manner. This gilding is easily burnished, and takes a fine polish; and it has been proved that friction from hard bodies, which would seriously injure ordinary gilding, does not affect it.

M. Grenon's method merits attention from the public on account of its solidity and brilliancy; the increase in price (which is not very considerable) being justified by the quantity of gold employed, and the double expenses of laying-on and burning.


Scientific Notices. On a new coloring matter called wongshy.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

By M. W. Stein, of Dresden.

[Translated for the London Journal of Art s and Sciences.]
Towards the close of last year a substance, bearing the name of Wongshy, was imported from Batavia into Hamburgh, with the view of being employed as a yellow dye. As no account has yet been published, relative to the application of this substance to the purpose of dyeing, the following particulars may, perhaps, prove interesting.

The new coloring matter consists of pods of seed, obtained from a plant, which, according to M. Reichenbach, belongs to the gentian family. The pods, which are unilocular, jure of an oblong form, ovoidal, and terminating in a point on that side near the []obtuse at the opposite extremity, and surrounded by the calix, which is dry and has five divisions. They vary in size, which is generally from 1 J to 1 J inches in length, with a diameter (in the largest part) of about half an inch. The color is a reddish-yellow, which is not uniform; it being darker in some places than others. The surface is more or less irregular and wavy, with from six to eight longitudinal nerves. It has a smell somewhat like saffron, with an after smell of honey. The shell is hard and brittle, and on being masticated it quickly becomes mucilaginous and colors the saliva yellow, giving out a slightly bitter flavor. It swells considerably in water. Inside the pods are small seeds, of a deep reddish color, and having a rough surface; they are detached from the sides, and are closely imbedded in a hard pulp: as many as 108 of these seeds have been counted in one pod. These seeds are rather hard, being chewed with difficulty, and having no particular flavor; but leaving on the end of the tongue a peculiar burning sensation, sweet and stinging, which is similar to that of red paraguay: the pulp in which they are imbedded has a strong bitter taste, which is most perceptible at the back of the gums.

The embryo, which consists of cells, containing amylum, is surrounded with albumen; the amylum may be easily detected by means of iodine, which partially colors the embryo blue, but does not affect the mass surrounding it. On being properly prepared and viewed under the microscope, this embryo presents two cotyledons; and its structure is more particularly seen on making a transverse section of the seeds passing through the em bryo. It is also to be remarked that the amorphous coloring matter, which is yellow in the cells inside the pod, with a slight tinge of green, appears of a purple red in those placed outside.

The wongshy fruits (when ground, both at the ordinary temperature, and at the boiling point) give up to water their coloring matter, which is of so divisible a nature, that two parts of the ground pods furnish 1 28 parts of a liquor which, on being intro duced into a cylindrical vessel of white glass, 2^- inches in diameter, displays, when exposed to the light, a clear yellow color. The concentrated extract is very mucilaginous, and is of a fire-red color, which disappears when the liquor is much diluted, and is converted into a gold-yellow. Alcohol, at 80° Centigrade, and also pure alcohol, on digesting pulverized fruit in it, also acquires a fire-red color, which is, by dilution, converted into gold-yellow. On digesting it in ether, it is, at the ordinary temperature, colored variously from pale up to brownish-yellow, and leaves, after evaporation, a thick yellowish-brown oil, which has a fruity smell and a sweet taste, slightly bitter; and which at 0° only deposits a small quantity of concrete fatty matter: on being agitated with azotate of protoxide of mercury, it does not thicken, even after a length of time; and consequently may be classed amongst the siccative oils. By saponification, perfectly colorless fatty acids may be extracted from it. The color of this oil is therefore due to a small quantity of the coloring matter which it has carried off with it.

Fatty oils do not possess the property of extracting any portion of coloring matter from these fruits, either at the ordinary temperature, or with the addition of heat.

An aqueous solution is obtained, in the form of jelly, by the addition of alcohol. This jelly, which is of a yellowish color, may be rendered perfectly colorless by washing with alcohol. On drying, it forms a translucid mass, which is slowly dissolved by water,—forming a thick mucilage. (In one experiment made by M. Stein, in which it was extracted from a fermented solution of the coloring matter, it was not obtained in the gelatinous form, but in the form of soft flakes, which, after drying, remained white and opaque, but otherwise behaved in the same maimer as the translucid substance.) This solution is not precipitated by acids; caustic soda, in excess, produces a gelatinous deposit; and when the soda is only in small quantity, the liquor remains limpid; but the addition of acid immediately produces gelatinous flakes. Carbonate of potash behaves in the same manner,—excepting that a considerable time is required for the production, by an excess of that salt, of the gelatinous thickening of the liquor, and that acids only produce slight flakes. Water of baryta precipitates the solution so completely, that the liquor from which the precipitate has been separated by filtration, on being submitted to evaporation upon a sheet of platina, and the residuum calcined, presents no traces of organic matter.—Lime water also produces an analogous precipitate, and acetate of lead produces a gelatinous precipitate.

The manner in which this substance behaves, and which has just been mentioned, agrees with the properties of pectine, as described in a recent work of M. Fremy; it will therefore be seen that wongshy contains a considerable quantity of pectine.

If, after having deprived the liquor of pectine by means of alcohol, a small quantity of acetate of copper be added, and caustic soda in excess, protoxide of copper will be precipitated. This substance, therefore, contains sugar, the presence of which is also manifested by the fact, that on exposing it in a pulverized state, and diluted with water, to a moderate heat, alcoholic fermentation will take place. During this fermentation, which, in one experiment, lasted more than three weeks, carbonic acid was disen gaged in large quantity, together with, at first, an odour of beer, which afterwards changed to that of butyric and valeric acids. On afterwards submitting the fermented liquor to distillation, a product was obtained which did not contain any alcohol, but only traces of acetic and butyric acids. In the liquor which remained, neither lactic acid nor mannite was detected. These phenomena of fermentation differ materially from those presented oy what is called viscous fermentation; by which, as is known, sugar is decomposed into carbonic acid, gum, lactic acid, and maunite, without the formation of alcohol.

* One experiment made by M. Stein, for the purpose of ascertaining whether with alum, and by precipitating with potash, a fine lacker might not be produced, did not give satisfactory results; as by this means only a small portion of the coloring matter, combined with the alumina, was precipitated, which was entirely removed hf simple washing with water.A solution of gelatine produces in the aqueous extract a trace of precipitate, arising from the presence of tannin. Chloride of tin, at the ordinary temperature, does not, even after the lapse of considerable time, produce any change; but, on raising the temperature, a precipitate of a deep orange color is perceptible. Basic acetate of lead produces no change. Simple acetate of lead produces a slight cloudiness at the ordinary temperature, and an orange precipitate at the boiling point. Sulphate of iron changes the color to a deep brown-yellow, without any precipitate being formed, either in the hot or cold state. Alum,* acetate of alumina, and acetate of zinc, give yellow precipitates, but only in the hot state. Baryta water, even at the ordinary temperature, produces a yellow precipitate, which, on being boiled, turns to a reddish tint. Lime water furnishes a yellow precipitate, which is not changed by heat, Solutions of sulphate of lime and chloride of calcium give no precipitate, either in the hot or cold state. Spring water, containing a considerable quantity of car bonate of lime, did not precipitate the coloring matter, even with the addition of heat; this latter is, therefore, unable to decompose combinations of lime with acids.

With regard to the solution of the coloring matter when completely deprived of pectine, water of baryta and of lime act rather differently,—as orange precipitates are formed at the boiling point. Caustic soda, caustic ammonia, and carbonate of potash render the color darker and tinge it brown. This change is not due to the coloring matter itself, but results from the action of the alkalies upon the sugar of gelatine which is present; and also upon a very bitter and easily changed substance which could not be separated. At the same time, on boiling the liquor and employing carbonate of potash or caustic soda, the disengagement of ammonia will be perceived on testing it by holding litmuspaper over the mouth of the vessel Nitric acid, in small quantity, and at the ordinary temperature, does not produce any change in the liquor; but when this acid is added in larger quantity, it causes the red color of the liquor to disappear; which then appears limpid, although slightly tinged with red. Each drop of acid, on falling into this liquor, causes it to assume a greenish tint, giving to the matter a distant resemblance to saffron yellow, which is also turned green by nitric acid. Sulphuric acid of commerce, in the cold state, produces a brown-yellow, and in the warm it is a yellowish-green by transmission, and a deep green by reflection. After the lapse of some time, olive-green flakes are separated, whilst the liquor appears of a reddishbrown color. Hydrochloric acid does not produce any change in the liquor at the ordinary temperature; but, on being heated, and before reaching the boiling point, it appears of a yellow-green color by transmission and deep green by reflection. Soon afterwards deep green flakes are precipitated, and the liquor becomes of a reddish-brown color. This reaction, which distinguishes the extract of wongshy from solutions of all other known yellow coloring substances, is not caused by the pure coloring matter, but by the bitter substance above mentioned; and for this reason this test must not be employed for ascertaining whether fabrics have been dyed with wongshy, as the bitter substance does not combine with the fabric. Tartaric and citric acids change the color to a brown-red. Metallic zinc, with the addition of a few drops of hydrochloric acid, decolors the liquor, changing it to a pale yellow, which colors woollens but very slightly. The liquor does not recover its former color on exposure to the air. Sulphurous and hydros ulph uric acids only produce imperfect decoloration of the liquid;—complete decoloration is obtained with difficulty, even by the action of chlorated water.

In order to ascertain with certainty whether wongshy could be employed for dyeing, M. Stein infused a quantity of the pulverized pods in lukewarm water for twelve hours—stirring frequently; after which, the liquor was run off. In this manner the coloring matter was extracted in the most expeditious manner, without the liquor becoming too thick or viscous, by the formation of paste, which would take place at the boiling point.

M. Stein states that, notwithstanding many experiments, he has not been able to produce a good green with wongshy yellow.With this extract, samples of woollens, properly prepared, were dyed, some without mordant, and others mordanted with alum, chloride of tin, acetate of alumina, and acetate of lead, in a bath heated to about 50° Centigrade, —as at a higher temperature the color is not pure.* The result was, that the unmordanted stuff was dyed, in a single bath, of a fine uniform orange color; and that amongst the mordanted samples, those treated with alum and acetate of alumina were better than those treated with chloride of tin; and that those having acetate of lead for a mordant, produced the least satisfactory results. The tone of the color was not changed by the three first-mentioned mordants; the samples were, however, dyed with a color less intense and less uniform. By means of a second bath, the samples treated with alum gave perfectly satisfactory results.

The coloring matter combines as readily with silk, and communicates to it a very brilliant gold color; so that M. Stein does not hesitate to give the preference to dyeing without mordants. Cotton, as might have been foreseen, will only take the color by means of a mordant; —the tin mordant appearing to give the best results. The color is an orange, very agreeable to the eye. This color, whether upon wool, silk, or cotton, resists perfectly the action of soap; alkalies, however, stain it yellow; and acids and salt of tin, turn it red. From the manner in which it behaves in these cases, it differs from annotto dye, to which it, however, bears great resemblance, as will be hereafter shewn,—the similarity extending to the action of the light upon the two bodies. This color, on being exposed to the light, very soon loses its color upon cotton, and a little more slowly upon wool: in this respect it appears to be more durable upon the unmordanted samples; but when employed for silk, it offers the most resistance; so that, compared with other yellow coloring matters, it may be considered to be one of the best.

On mordanting a woollen fabric with lime water, and passing it through a boiling bath of that substance, a fine yellow, inclining to red, was obtained, which resisted completely the action of soap, and also resisted the action of light better than the orange: alkalies, acids, and salt of tin, change it less than the orange, but in an analogous manner. Various fine shades of yellow may be obtained by adding to the bath carbonate of potash or caustic potash, and passing the unmordanted pieces through the bath at the ordinary temperature. The combination of the color with the fibre takes place very speedily, and with great uniformity and tenacity. By the addition of one part of potash to 30 parts of the coloring liquor, a yellow is obtained which is of a peculiar tint, owing to the presence of a small quantity of red. By doubling the quantity of potash, a bright yellow, inclining slightly to green, is obtained.—A larger addition of potash is not desirable, as the color becomes dull and uncertain. If caustic potash be used instead of the carbonate, a pure and lively yellow will be at first obtained, and containing little less red than that produced by the carbonate; and, afterwards, a fine canary yellow, with a slight tinge of green. Ammonia acts in the same manner as carbonate of potash and caustic potash; but the color is richer in red.— The coloring matter furnishes also somewhat different tints, when the fabric, after being washed, is passed through an alkaline bath.

The action of the alkalies is the same for silk and cotton; it is, however, a little less striking, as the fibres of silk and cotton absorb the coloring matter in less quantity than wool. The manner in which the coloring matter of wongshy acts, in common with annotto dye, is explained by the chemical character of the former, which is presented as a weak acid. It is from this circumstance that it has a disposition to combine with alkalies, and even with alkaline earths, as is shewn by the precipitation by waters of baryta and lime. The combinations which it forms with the former possess a pure yellow color, and are decomposed by the more energetic acids: when the coloring matter is thus set free, it assumes a lively cinnabar red. The matter, thus eliminated, is not the same as that which was originally in the aqueous solution, as it has become completely insoluble in water, and is only dissolved in small quantity by pure alcohol, ether, and alcohol at 80° Cent., which it colors yellow. Its color in the damp state is a cinnabar red; in a dry and most pure state, a brownish-red; and, like extract of ratanhia, it is easily reduced to powder; but, when it contains sugar and fatty matter, it pre sents, if inspected in thick layers, a fine yellow color; and, while in thin layers, it appears yellow and translucid, and draws humidity from the air. When the pure matter is heated on a sheet of platina, a yellow vapour is first disengaged, and the color is, in some places, pure yellow; it subsequently changes to a black, melts, and becomes carbonized. The resulting ash is very combustible;—the yellow vapours condense in yellow oily drops when the experiment is conducted in a small glass tube. Concentrated sulphuric acid brings out a faint blue, and the acid is colored with the same tint, which passes speedily to violet and brownred; whilst the coloring matter is slowly dissolved. With water, a flaky precipitate is formed, of a dirty yellowish-grey.

* To obtain it pure, with the etherieal solution, M. Stein evaporated the ether and treated the residuum with an aqueous solution of marine salt, in order to separate the fatty matter, which was then filtered off; the liquor was then evaporated at 50 per cent., and the residuum removed by means of alcohol. On afterwards evaporating the alcohol, a brown residuum was obtained, which had no bitter taste, and was insoluble in water.

** M. Stein remarked, in one instance, in the solution, concentrated by evaporation by the aid of a magnifying glass, detached white crystals, and others in the
The change of annotto to a blue tint by the action of sulphuric acid has no analogy with the phenomena presented by the coloring matter of wongshy, as the liquor is never, as is the case with annotto, colored a pure blue, but only presents traces of it—being violet for an instant only. It is easily soluble in ammonia and caustic soda, to which it imparts a gold color. In order to obtain it pure, an extract is made, by means of pure alcohol, from the bruised pods of wongshy; the alcohol is then separated by distillation, and the residue is treated with ether (to deprive it of the fatty matter), and afterwards dissolved in water; the solution is then treated with basic acetate of lead, with the addition of ammonia, and a precipitate is obtained. The plumbic precipitate, after being well washed and diluted with water, is afterwards decomposed by hydrosulphuric acid. On afterwards heating the liquor separated from the sulphuret of lead by the hydrochloric acid, it will be colored green; and, on evaporating it, a brown substance will be obtained, insoluble in water, and which is probably a product of the decomposition of the bitter substance above mentioned; a great part of which will, together with the fatty matter, have been carried away by the ether.* If, after drying the sulphuret of lead, it be treated with pure alcohol, it will assume a yellow color, and give up, by evaporation** the cinnabar red coloring matter, which is afterwards changed to brown-red. The product is, however, so small, that the quantity obtained by M. Stein did not allow of an elementary analysis being made. Nevertheless, by the help of M. Levol's method of testing, M. Stein ascertained that it did not contain any azote, neither could any traces of sulphur be detected on boiling with caustic ley.

The insolubility of the coloring matter in water, after being separated from the basic oxides, in contradistinction to its easy solubility before entering into combination with those oxides, led M. Stein to make some experiments, with the view of discovering the explanation of this phenomenon. One proof, that neither sugar nor pectine, in any way, influence the solubility of the coloring matter, is, that a solution containing sugar will, after having been boiled in caustic soda, allow the coloring matter to be precipitated, by means of vinegar; and this prepared and pure matter is neither soluble in a pure solution of pectine nor in a solution of sugar. One fact which seemed remarkable was, that the precipitation by acids took place immediately after having boiled an aqueous solution of the matter in caustic soda; while, at the ordinary temperature, a much longer time was required. M. Stein concluded from this, that the coloring matter originally existed in a state of combination, which was completely destroyed by boiling with the caustic soda. He supposes it to be an ammoniacal combination; for, as before remarked, a disengagement of ammoniacal gas was observed on boiling with caustic soda. This disengagement is, it is true, scarcely observable at the ordinary temperature; and, on the addition of chloride of platinum, even when the liquor is evaporated, no ammoniacal platinum is formed. This fact seems, therefore, to justify the opinion, that the coloring matter of wongshy is a starchy compound; and this opinion is supported by the fact, that the matter, after the solution has been boiled with caustic ammonia, cannot be precipitated by acids, but that it is capable of pecipitation from the aqueous solution, which still contains sugar, by boiling it with hydrochloric acid: in this case it should be remarked, that it is not of a cinnabar red color, but a brown-yellow, by reason of the pro ducts of decomposition of the sugar which were present.

M. Stein observes, in conclusion, that wongshy contains 5 per cent. of ash, which is obtained at a low temperature, and in an entire state, by mixing the pounded fruit with powdered platina. It was observed, in some experiments (in which plntina was not employed), that, at a certain temperature, there was, each time, sudden and violent combustion, which led to the belief that the fruit, perhaps, contained saltpetre. M. Stein, therefore, treated the fruit (deprived as much as possible of coloring matter by means of alcohol) with water, and endeavoured to detect the presence of nitric acid in the extract by means of sulphate of iron; he also treated another portion with sulphuric acid, but no traces were perceptible.

The ash of wongshy rapidly absorbs humidity from the air, and effervesces briskly with acids. On saturating it with nitric acid, M. Stein determined the proportion of phosphoric acid which it contains, according to M. H. Rose's process; i.e., by the help of mercury, and other ingredients usually employed.

100 parts of ash contain—
Phosphoric acid 10.27 = 5.75 0
Silica 400
Sulphuric acid 0.93
Chlorine 0.55
Lime 11.96 = 3.36 O
Magnesia 3.47
Oxide of iron 5.51
Soda 11.35
Potash 29.19

The solution of this ash, neutralized by nitric acid, is precipitated of a fine yellow color, by nitrate of silver; and the proportion of oxygen contained in the lime, bears the same proportion to that in the phosphoric acid as that contained in the basic phosphate of lime, according to the formula CaO x PO5. The question, whether these two matters are really thus combined, is left undecided,—M. H. Rose having perfectly demonstrated, in a recent work, how little one is justified in pronouncing upon the state of combination of the inorganic elements of plants from the analysis of their ash. The greater part of the basic oxide above mentioned must be combined with an organic acid, as it is found in the ash combined with carbonic acid. The quantity amounts to 21-67 per cent., supposing the alkalies to be in the state of carbonates, and the loss of 1.10 per cent. observed, to be really owing to the carbonic acid combined with the magnesia; which acid, on incineration in the presence of the alkaline carbonates, is but imperfectly driven oflf from the magnesia.


Scientific Notices. On the employment of peat charcoal in the arts.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

There is, perhaps, no subject of enquiry, relating to matters of industry, which has awakened more general interest, or given rise to more sanguine expectation with regard to its influence upon the condition of a certain class of the community, at least, in Ireland, than the application of peat, on an extended scale, as fuel for domestic purposes, and in some branches of manufacture.

The prominent manner in which this question has been treated by individuals, whose position is sufficiently elevated to give them credit in the eyes of the world, has probably led, in many respects, to a false conception of its true merits; at the same time, the extensive introduction of peat into use as a substitute for other descriptions of fuel, promises advantages too great to be treated of slightingly.

Peat, as is pretty generally known, is a substance of vegetable origin; a substance apparently still in a state of transition, still undergoing those chemical changes which sufficed, in the early ages of the world, to convert whole forests into the vast carbonaceous deposits encountered in certain localities, under the form of coal. The conversion of vegetable matter into peat, is a process which, under favorable circumstances, such as the presence of moisture and the accumulation of the vegetable substance in large masses, seems to be constantly in progress; and immense tracts of peat are doubt lessly, at the present time, in process of formation. Peat is met with principally in damp marshy districts, on the borders of rivers, the course of which is impeded, so that their waters become partially stagnant; and particularly in the neighbour hood of the embouchure of great rivers, which flow through a low country. It is also encountered, in some cases, at a great height above the level of the sea,—peat bogs existing in the elevated vallies of the Alps, and also in the mountain ous regions in the north-western part of South America.

In its natural state the use of peat, as fuel, is limited, both from its want of calorific power, and from its containing a large proportion of volatile matter, the odour of which is penetrating, and easily imparted to matters in its neighbourhood. When peat is, however, previously burned to charcoal, or, more properly speaking, to a kind of coke, it is converted into a fuel of most valuable character, nearly approaching, if not quite equal to, wood charcoal, and the coke from coal, and possessing some qualities superior to either of them.

In a country where, as in England, an apparently unlimited supply of excellent fuel can always be obtained without difficulty, both for the purposes of manufacture and for domestic use, we are apt to lose sight, or to become regardless, of the advantages that may be found in the conversion of a substance like peat to a useful object; but it ought to be borne in mind, that the coal measures are probably not exhaustless; indeed, it has been publicly stated, by an unquestionable authority on such a subject, that the day when England will see the end of her coal is not so far distant as we are disposed to believe; it is therefore, even in this respect, an object of interest to see the enormous tracts of peat which cover many square miles of country, rendered available to the ends of industry, even if it were only with reference to the economising the great source of our national supremacy. With respect to the employment of peat-charcoal, there are some circumstances to be considered which serve to give it a fair title to superiority over both wood-charcoal and coke: in its application to metallurgic processes, for example, particularly in the manufacture of iron, its superiority is well marked; and in many manufacturing processes, where a continued moderate heat is requisite, this kind of fuel is very much better than either coke or wood-charcoal. The value of peat-coke, as fuel, arises from its peculiar composition; and partly from its physical character. Owing to its being somewhat friable and cavern ous, it ignites readily, and, when once lighted, burns entirely away, even when in small fragments. The amount of heat it produces in burning is somewhat less than that of wood-charcoal, weight for weight; and it bears almost the same relation to coke; but it is more lasting than charcoal, and, from its chemical constitution, more suitable to metallurgic purposes than coke. Most varieties of coal contain sulphur in the form of iron pyrites, and some, sulphate of lime also, which, as well as the pyrites, is a source of sulphur, as it becomes converted into sulphuret of calcium in the process of coking. Now, in almost all metallurgic opera tions, the presence of sulphur is highly deleterious, as it is apt to form a combination with the metal under treatment, and so produce an injurious effect. This defect; when coke is used, attains a high pitch, unless the coke be prepared with great care and skill, so that the sulphur may be partially expelled or burned off during the process of burning: in coke prepared in retorts, or in gas-making, the presence of the sulphur is an effective bar to its employment in the arts. The objection arising from the noxious influence of sulphur cannot certainly be urged against wood-charcoal; but this substance possesses, when compared with the coke from peat, a physical disadvantage: — from its light porous structure it burns away with great rapidity; and (although, from its purity, well suited to almost every operation in the arts) on this account it becomes too costly to be employed, excepting under circumstances in which no substitute for it can be made by coke or other fuel. At all times charcoal must be a very costly fuel, both in consequence of the limited supply of the raw material, and from the expense of manufacture. Peat-coke offers a substitute for charcoal under all circumstances, and under almost all for common coke as well. Peat seldom contains sulphur in any state; and even when that substance is present, it is in such small quantity that it is generally oxidized and expelled in the process of coking the peat.

After having been dried, peat yields, when burned, about twothirds of its weight of coke equal to wood-charcoal; and it has been calculated that this may be produced and sold for about 35s.per ton; at which price it would compete, in the market, with coke from coal, and possess a great advantage in price over charcoal;—in this case, we suppose the peat-coke to be prepared according to the present method of burning charcoal, or of making coke from coal in ovens. Peat contains, how ever, a certain proportion of matters having commercial value, which, being volatile, are driven off during its combustion, and, consequently, lost; these are, acetic acid, ammonia, and certain volatile oils, partaking of the nature of naphtha. See ing that these valuable matters are lost in the process of carbonizing the peat in ovens, it has been proposed to carry on the process of conversion in retorts of brick or iron, to approximate the process to the manufacture of gas from coal, or that of the extraction of acetic acid and other products from wood. This idea does not, however, with respect to peat, appear to possess much practical value; it is a question whether the quantity of the products above named be sufficient to cover the increased expense of working;—for, in the first place, the amount of peat-coke produced at each opera tion is reduced, inasmuch as the retorts must be limited in size; and, secondly, a great additional expense is incurred for fuel to heat the retorts, which, being closed from the air, require to be heated entirely from the outside; and, as a given quantity of peat requires the consumption of a quantity at least equal to its own bulk, to burn it into eharcoal, it is clear that one-half of the charcoal from the whole will be lost; and is to be compensated for by the volatile products collected from that peat contained within the retort;—the process being also in every way more laborious, and, consequently, more expensive. In the process of coking the peat in ovens, the peat burns itself,—the volatile matters are certainly all lost; but every ton of peat yields its proportion of coke, which is its most valuable commercial constituent.

In the manufacture of iron, it is a question whether peat-charcoal may not be entirely substituted for every other kind of fuel with striking advantage to the manufacturer, with respect both to the quantity and quality of the iron produced. It was suggested long ago by Berthier that peat might be used with advantage in the extraction of iron from its ores; and he also hinted at the advantage that might be gained by mixing the pounded ore with the charcoal, compressing the whole into the size and form of bricks, and thus placing them in the furnace;—the iron ore and carbonaceous matter would thus be brought into a degree of proximity that would probably much facilitate the reduction and fusion of the metal—at the same time that a fuel was employed incapable of producing upon the iron any injurious effect.

The employment of a fuel derived immediately from the sterile bogs which cover so many thousands of acres of land otherwise available to agriculture, would be in itself an in ducement to promote the introduction of peat-charcoal into more general use; but happily the benefit would be here as much to the arts adopting the innovation as to the agents of its immediate production.

T. W. K.


Transactions of the Society of Arts. February 13th, 1850. Mr. George Wallis read a paper on the present condition of art as applied to calico printing.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

Mr. Wallis commenced by referring to the paper read by him to the society last session, in 'which he endeayoured to trace out the past progress and present condition of calico printing, so far as related to the mechanical and chemical departments; he then proceeded to give a general outline of the subject, and to call at tention to a scries of illustrative specimens, shewing the limits to which design is subject when applied to particular fabrics.

The mechanical means generally employed in printing calicoes are blocks and cylinders, and the colors are "madders" and " steams." Of the class of fabrics on which steams are usually employed, mousseline-de-laine was mentioned as a type; while the prints usually known as Hoyle's are distinct examples of madders. The madder dyes, properly executed, are essentially fast, and the tints are only to be reduced by repeated boilings and washings,—a course frequently taken by the printer to get his color down to the desired hue. The fast colors are the following: red, ranging in tint from dark crimson to light pink; purple, ranging from the darkest tint to the lightest shade -, chocolate; brown; and black. Besides these madder colors, there is a fast blue, produced from indigo and catechu brown: thus, with the exception of yellow, and consequently green of a brilliant tint, the range of fast colors is complete. In steams there is a wider range of colors (including green, yellow, orange, &c.), with less permanence of tint; but in de-laines these may be considered as fast, —wool having a much greater affinity for coloring matter than cotton.

The author next proceeded to call attention to the nature of the designs suitable for madders, and first referred to mill-work, in which each roller is necessarily limited in size from two-and-a-half to four inches in circumference: this gives the size of the repeat of the pattern. The class of designs best suited to this process of manufacture is that of stripes, as they are easily engraved and readily printed: striped patterns should be varied not so much in form as in disposing the groups upon them.

The artistic effect of the details is only limited by the number of cylinders; but the author is of opinion that the most agreeable effects can be produced with two or three tints; as true artistic feeling is quite consonant with simplicity in materials.

Mr. Wallis next referred to the extent to which the effect of relief might be successfully carried. The best art is that in which the art is most concealed: on seeing a lady's dress, or a furniture print, the sentiment of the whole ought to strike us, without any portion being so obtrusive as to cause special enquiry as to what it is or how it is produced. Of the effects producible in madders, the monochrome is the most suitable. A flat relief is very effective for half-mourning. All the various processes of en graving are applicable for the production of different effects: where the repeat is small, mill-work is used; and where it is large, the cylinder is engraved all over by hand, and a "cover" added by the etching process.

Steam colors constitute the great mass of productions in calico printing, particularly for the foreign trade. The range of these colors, capable of easy introduction, offers a great temptation to the designer to supply his want of artistic effect by showy vul garity; and thus, while madders are usually confined to two or three cylinder machines, steams occupy as many as four, five, six, and in some instances seven cylinders.

The author then cautioned designers against crowding their patterns for the sake of introducing several colors; and he proved, by examples, that freedom of treatment is compatible with perfect accuracy of execution. He further urged the pro priety of more closely studying nature, both for harmony of colors and for elegance of form: the former shewn so variously in the skins of animals, in shells, flowers, leaves, and insects; and the latter in the growth, interlacing stems, &c., of grasses and other vegetables—amongst which the ability of the artist in selection and combination will find a wide field for exercise. Mr. Wallis next glanced at what he termed "de-laine" effects, including mousselines-de-laine, muslins, and bareges,—all of which he classed under the general head of calico printing. The best specimens are chiefly block-work, which affords a wider range of pattern and a larger number of colors than can be got in mill-work; but five may be said to be about the average. Attempts have been made to combine block with cylinder work, but the effect is rarely satisfactory; and, on account of the mechanical difficulty of the combination and the cost of produc tion, it may now be said to be abandoned.

The author concluded his paper by calling attention to the various specimens and designs upon the walls, and to the new application of printed calicoes to panelling and internal decoration.


Ornamental Glass. 1. Colored Glass.

Manufacturer and Builder 7, 1875

Glass is colored with metallic oxids by two different methods; in one instance the sheet is colored throughout and blown as usual from what is technically termed "pot metal." In the other instance the workman dips his blowpipe, first into colored and afterwards into white glass; when the compound mass is blown out both glasses expand together and a sheet is formed of two layers, one (generally very thin) colored and the other white. On looking through this socalled flashed glass, there is no perceptible difference between it and the pot metals, but the distinction is easily seen by looking at the edge.

All the colors are occasionally made in this manner, but copper ruby glass is always flashed, because it is naturally much too deep in color to allow of its being blown of the ordinary thickness; the layer of ruby glass, or even the darkest sheets are seldom thicker than common letterpaper, the substance of the pane being white glass. These thin colored strata of the flashed glasses are easily removed from the surface by wellknown methods of glass-cutting and engraving, or by etching with the aid of fluoric acid. White patterns on colored grounds, or the reverse, are thus readily produced, many of them, especially in the finely cut and engraved ones, being of exceeding beauty. Unfortunately it is impossible, by any illustration, to give the remotest idea of the brilliancy and life of these designs.

The colors just referred to are produced while the glass is in the furnace, and of course before it is blown into sheets; but by the process of staining all the various tints of yellow, from a faint tint of lemon through full yellow and orange, up to a somewhat brownish red, can be imparted to the glass after it is blown. This process depends upon a peculiar property of silver, which is generally employed in the form of the chlorid, (horn silver,) and is mixed and ground with some inert substance, as oxid of iron or pipe-clay. The mixture or stain is floated over the article to be colored by time aid of seater or spirits of turpentine, and when dry the coating is about the thickness of cardboard. The glass is then brought gradually to a full red heat, and afterwards annealed; during the operation the silver penetrates .d actually dyes or stains time glass, the oxid of iron or clay remaining loose upon the surface. The color thus obtained is perfectly clear and brilliant, and the surface of the glass appears to have undergone no change, so that finished cutglass goblets and vases can be colored entirely or (by very simple and apparent modifications of the process) in any device that may be desired. The intensity of the stain is in proportion to the quantity of silver in the mixture and the degree and duration of the heat; but the darkest and richest tints can only be produced on glass made for the purpose.

This property of silver is invaluable to the ornamental window painter; it enables him to produce colors, although his choice is limited, into designs executed upon common windowglass, and by using flashed glass and partially removing the layer of color by etching with hydrofluoric acid, lie can stain the white glass thus laid bare, and is a step nearer the solution of his grand difficulty—the production of various clear and transparent colors in the same piece of glass.

The colored glass paints never possess the clearness and richness of the colors already described. These glass paints are made of very fusible glasses ground and mixed with oil of turpentine; they are laid on with a brush in the usual manner, and when sufficiently heated, melt and fasten to the glass, but never become quite clear and transparent. The difficulty. of insuring even moderate success in glasspainting is mainly owing to the great and often apparently capricious alterations which the colors under-go in baking; time shade or opaque colors always vary in tint as they are seen by reflected or transmitted light, and when to these obstacles is added the wellknown brittleness of the material, it is scarcely surprising that time longest experience and most practiced care can not always avoid disappointment.


Scientific Notices. Red color for paper-hangings, &c.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

It is proposed to employ the red chloride of chrome for the production of an intense red violet color, possessing metallic lustre, proper for printing or staining paper.

This product is prepared, as is well known, by passing a current of dry chlorine gas over a mixture of powdered charcoal and calcined oxide of chrome, enclosed in a glass tube. Attention must be especially given in this operation to the fact that, by reason of the difficulty of volatilization of the product, the chloride prepared by a first operation remains mixed with the powdered charcoal. It is, therefore, requisite to submit this mixture of charcoal and chloride of chrome to a second operation, taking care to cover the bottom only of the glass tube with it,—in which case the product will be sublimed in the upper part of the tube. The heat of an argand lamp, the flame of which is brought gradually upon the tube, will suffice for the formation of the chloride, which soon appears in the form of brilliant micaceous peach-colored spangles. The chloride is then ground in a mortar, and thickened with a mucilage of gum. On being laid upon paper it will display its original color, and will resist the action not only of acids and alkalies, but also the direct action of the solar rays.


Scientific Notices. Report upon the manufacture of ceruse or white lead, as regards its effect upon the health of the workmen: prepared for the Academy of Sciences, Paris.

The London Journal of Arts, Sciences, and Manufactures, and Repertory of Patent Inventions.

Conducted by Mr. W. Newton, of the Office for Patents, Chancery Lane. (Assisted by several Scientific Gentlemen.)

VOL. XXXVI. (Conjoined Series.)

London: Published by W. Newton, at the office for patents, 66, Chancerylane, and Manchester; t. and W. Piper, Paternoster Row; Simpkin, Marshall, and Co., Stationers' Court; J. McCombe, Buchanan St., Glasgow; and Galinani's Library, Rue Vivienne,

Paris. 1850

By M. Combes.

[Translated for the London Journal of Arts and Sciences.]

The maladies to which manufacturers of white lead, as well as those who are engaged in preparing or using pigments or other preparations having lead for their base, are peculiarly liable, have for a considerable period excited the attention of scientific men, and particularly that department of the government having the public health more especially under its care.

It is well known that, in 1783, Guyton Morveau proposed to substitute zinc white for white lead in the preparation of pigments; but all attempts made for that purpose, from that period to the present time, have in great part failed, either from the high price of the zinc white, or from other causes, which form no part of the subject under discussion in this report. M. Leclaire recently undertook the manufacture of oxide of zinc on a large scale, in order to apply it to painting vessels and to other purposes.

On that occasion statistical documents, extending over a considerable period, and collected from the hospitals of Paris by the Council of Health of the Department of the Seine, touching the maladies under which workmen using lead or preparations of lead suffer, were very extensively circulated. From these documents we learn that, during a period of ten years (i.e. from 1838 to 1847 inclusive), the hospitals received 3,142 patients, of which number 1,898 came from two manufactories of ceruse or minium, in the Department of the Seine. MM. Theodore Lefebvre&Co., and Poelmann Brothers, manufacturers of ceruse on a very large scale, in the environs of Lille, struck with the injurious effect it must necessarily have upon their business, addressed to the Academy certificates from medical men, and a report from the central Committee of Health, in the Department du Nord, stating that, in consequence of the improvements made in the process of manufacture, and the attention paid to the health of their workmen (150 in number), none of them had been attacked with cholic for upwards of a year. MM. Lefebvre and Poelmann concluded, by requesting the Academy to verify the facts by means of a Commission, to be appointed for that purpose.

In order to carry out this object MM. Lefebvre and Poelmann' s manufactory was visited, and also the white lead manufactories in the Department of the Seine, and all those in the environs of Lille, one only excepted. From the information thus gathered we shall shew the various improvements introduced into many of these establishments, and at the same time point out what is further requisite. We generalize our observations, leaving to the proper authorities the task of prescribing to each manufactory the improvements necessary for the health of the workmen, persuaded, as we are, that a sense of humanity will prompt the manufacturers to anticipate any orders to that effect.

White lead is generally manufactured in France by what is called the Dutch process; in a manufactory at Clichy, however, the French process (established by M. Roard, according to the instruction of M. Thenard), is partially used, for the purpose of improving the carrying on of a portion of the manufacture which it is very difficult to deprive of its injurious effects, viz., the preparation of oxide of lead or massicot in reverberatory furnaces. A very strong draft even is insufficient to protect the workman against the plumbic vapors; as they are constantly occupied in stirring or raking the oxide of lead formed, in order to lay bare the surface of the metallic bath. The succeeding operations, up to the potting of the white lead, are innoxious,—being performed by the wet method. The processes of drying and pulverizing the cakes of white lead are common to all modes of manufacture.

The Dutch process comprises the following operations: — 1 st. Fusion, and casting of the lead into plates of any required thick ness, or into bars of a long rectangular form. 2nd. Laying the lead in alternate layers with dung or tan. The lead is placed upon pots containing dilute acetic acid. It remains in the chambers thus filled for from thirty-five to forty days when dung is used, or from sixty to ninety if tan be employed. 3rd. The layers of lead (converted for the most part into carbonate) are now successively uncovered, and the white lead formed is removed from the metallic lead; after which, the white lead is ground and sifted, in order to remove any portions of metallic lead which may be mixed with it. 4th. Grinding up the white lead with water. 5th. Moulding and drying. 6th. Pulverization and dry-grinding of the cakes of white lead; sifting, and packing into casks, the white lead intended to be sold in the state of powder. 7th. For white lead which is intended to be sold in the state of paste, mixed with oil,—mixing the powder produced by the dry-grinding (without previous sifting) with from 7 to 10 per cent. of its weight of oil. The mixture is effected in a close vessel, by means of an agitator; after which it is passed through several pairs of cast-iron rollers. The fine homogeneous paste, thus produced, is received in a vessel containing water, from which it is taken and put into casks for sale.

lst. The melting of the lead.—This is performed in a cast-iron vessel, and no hurtful vapors are produced unless old lead be introduced, which has been used in previous operations, and is therefore covered with a layer of carbonate. In well-conducted establishments the melting vessel is placed under a flue or funnel, in communication with the chimney of the furnace, or any other chimney having a good draft. The platform of the furnace is connected with the flue or funnel by means of an outer casing of iron, of any convenient shape, and having doors or openings for the purpose of supplying the lead to be melted, or running the melted metal into moulds. These precautions appear to us to be sufficient to protect the workmen from injurious vapors. Besides, the melting of the lead is only effected at very long intervals.

2nd. The placing of the sheets or bars of lead in alternate layers with dung or tan.—From this operation the workman is not in the least exposed to injury. In all the French manufactories, one only excepted, the lead is cast in sheets; and in each of the pots containing acetic acid is placed a thin sheet, rolled in a spiral form, and bearing upon two supports near the bottom of the vessel. In one of the manufactories in the Department of the Seine, the lead is cast into bars, which are placed in beds, upon pots of less depth than those generally employed, and which do not contain rolled lead.

3rd. The separation of the carbonate from the metallic lead, and the pulverization and sifting of the same.—These operations constitute the most injurious part of the manufacture. In all the establishments which we visited, with the exception of one, these operations were performed as follows: —The workman first detaches the large scales or crust of white lead, which adhere very lightly to the metallic lead; he then takes in his hands the sheets of lead covered with ceruse, unrolls those which were placed in the pots, twists them about in various directions, and puts on one side the detached scales. This operation, which is called picking (epluchage) in the Department du Nord, is sometimes performed in the place where the layers are formed, and sometimes in another, into which the sheets covered with white lead are carried, just as they come from the beds. The picking operation, in which the operator has his hands constantly covered with carbonate of lead, is not, however, the most unhealthy part of the manufacture, as the white lead is detached in thick scales, which produce very little dust; but the sheets of lead are still partially covered with some portions of white lead, which adhere very firmly.

The old method of detaching these was by placing a pile of the sheets of lead upon a slab of stone, and striking the lead with a wooden beater; by this means the white lead was caused, either to fall off in the shape of minute scales, or else it rose in the shape of dust into the air, and was respired by the operator. This operation, which is still carried on after the old method in some establishments, is called scouring (decapaye) in the Department du Nord; but when so conducted, is extremely injurious to health. The scouring operation is now, in mauy manufactories, performed by mechanical means, which render it much less injurious than heretofore. The sheets, covered with adherent white lead, are carried in a hand-barrow to the scouring machine, and the operator takes them, one by one, and lays them carefully on a travelling endless-cloth, by which they are carried to the top of an inclined plane, down which they slide to an arrangement of apparatus, consisting of two pairs of longitudinally-grooved pressing- rollers, beyond which an inclined sieve is situated. Between these rollers the sheets of lead are made to pass, in order to detach the white lead therefrom. When the sheets of lead have arrived at the lower part of the sieve, they are received into a wagon, and pass away into a contiguous chamber. The white lead, which is detached from the sheets of lead, falls from the rollers upon a travelling-cloth, and is conducted to a hopper, together with the white lead which falls from the sieve; and the whole is delivered by the hopper into a wagon, placed in a chamber having closed doors. All the parts of the apparatus are en closed in wooden cases, which are kept shut during the working; there being but one opening, viz., that for allowing of the operation of the endless cloth, which feeds in the lead. The wagon containing the white lead is run out of the chamber as soon as the operation is completed and the dust has ceased to fly about; and its contents are added to the products of the picking operation, in order to be submitted to dry-grinding. This latter operation is mostly performed with vertical stones, turning in horizontal troughs. The white lead, when ground, is poured into the hopper of a fine bolting-cylinder, enclosed in a casing; into which the powder falls after passing through the meshes of the bolting-cylinder. Any scales of lead which may also have passed through the stones, will fall to the bottom of the bolting-cylinder, and from thence into a separate receptacle. The white lead, thus sifted, is mixed with water, and again ground.

In several manufactories in the environs of Lille, the pulveriza tion of the scales is effected by means of several pairs of horizontal cylinders, fluted in a direction transverse to their axes. The substance ground falls on to one or more metallic sieves; after passing through which, it is conducted by hoppers into a chamber, supplied with several jets of water. The scales of lead which cannot pass through the sieves fall into another chamber. The whole apparatus, consisting of grinding-cylinders and sieves, occupies the height of one story, and is enclosed in a wooden casing, furnished with a hopper above, which is kept full of scales of white lead, in order to prevent the dust from rising: the hopper may, if thought desirable, be closed by a trap. This arrangement constitutes one of the most important sanitary improvements upon the old system of manufacture.

In the manufactories of the Department of the Seine, in which the lead is cast in bars, instead of being operated upon in rolled sheets, the picking, scouring, pulverizing, and sifting operations are performed mechanically, by means of successive apparatus, enclosed in one casing, and divided into several compartments, connected together by wooden channels.

The first compartment or chamber contains three pairs of fluted rollers, which effect the picking and scouring of the bars; and also three other pairs, which effect the grinding of the scales. There are two openings at opposite sides of this chamber; one of which admits the endless-cloth, upon which the bars incrusted with white lead are fed in; and the other, through which the bars, after being cleansed, make their exit by sliding down an in clined plane of perforated sheet-iron, which is shaken at intervals by suitable mechanism. On leaving this compartment, they are straightened by beating with a wooden beater, and sorted; those which are fit for use again are selected and put aside; while those bars which are in great part decomposed, are melted and re-cast. The scales, on being detached by the action of the three pairs of fluted rollers, between which the bars successively pass, fall upon a moveable endless-cloth, extending under the cylinders, and also under the perforated iron plate; this cloth feeds the scales of white lead to three pairs of plain rollers, by which they are ground. The powder falls upon an inclined plane, and from thence into a casing, where it is received into vessels, attached to an endless band, and carried thence to the upper part of a second chamber, united to the first by the wooden channel, in which the endless-band, carrying the buckets, works. This second chamber contains the bolting-cylinder for sifting the white lead, and separating it from any scales of metallic lead which may have become intermixed with it: these latter are conducted into a separate com partment. The white lead falls to the bottom of the chamber, from whence it is afterwards taken (when the operation is completed and the dust has ceased to fly) and ground with water. In the operation just described, the workmen who receive the bars of lead, on their leaving the chamber, are still exposed to the injurious influence of the white lead powder; they are therefore made to work at this dangerous post by turns—each man being thereby prevented from working consecutive days.

The separation of the scales of white lead from the metallic lead, and the grinding and sifting of the same in a dry state, cannot be considered as salubrious operations under any circumstances; notwithstanding the important improvements which have been made upon the old methods, and the sanitary precautions taken in most of the establishments visited. Thus, the picking by hand of the scales of white lead from the metal, is attended with a certain degree of danger; attempts to obviate which have been made by several manufacturers, by causing the workmen to wear gloves. This precaution is, however, not merely insufficient, but it is attended with disadvantage, as the work cannot be so well performed as by the bare hand.

In the only establishment in which the picking is not manually performed, the bars of lead, on coming from the chamber, after passing through the rollers, still retain some portions of carbonate of lead, which are reduced to fine powder when the bars are beaten straight. This fine powdered white lead escapes from the chamber containing the grinding apparatus, either through the openings made purposely for the passage of the different substances, or through the holes in which the shafts of the mechanism work. All, or nearly all, insalubrity would be avoided in this manufac ture, if the separation of the scales of white lead, the pulverization, and the sifting, were performed under water; or, at least, if the ceruse and the residue of lead, on coming from the space occupied by the grinding apparatus, were received upon gratings or sieves, supplied with a number of minute streams of water, by directing a current of water through a perforated plate. According to the information furnished by M. le Play this would appear to be the mode of operation followed in England, where the residues of lead are again melted before being replaced in layers with the tan. We would call the special attention of manufacturers of white lead, and the government, to the importance of a method, the introduction of which appears to be attended with many ad vantages and but few difficulties; this is apparent from its being generally employed in England. The white lead would, by this means, undergo a washing, which would carry off, at least partially, the soluble salts by which its purity is injured; it is moreover necessary to dilute it with water, to submit it to the following operation

4th. Grinding the tohite lead with water.—The white lead is placed in tubs, and diluted with water, so as to form a soft paste. It is then passed successively through a series of horizontal stones, by which its trituration is completed. This grinding with water is perfectly innocuous. The workmen do not touch the paste with their hands; they merely pour it into the hoppers above by means of ladles.

5th. Moulding and desiccation of the white lead paste after being ground with water.—In all the manufactories, one only excepted, the soft paste is poured into earthen vessels of a conical form, which are exposed to the action of the air in a drying apparatus. By this means, a large portion of the water is evaporated; —the white lead acquires a certain consistence, and undergoes a contraction, by which it is detached from the sides of the earthen pots, and may be easily removed. The desiccation is then completed in a proper drying stove, by means of a current of hot air. The sides of the pots become covered with a layer of white lead, which is ordinarily removed with an iron scraper. This operation is performed by women or children, and is attended with inconveniences, which are sometimes obviated by cleaning the pots with water; this, however, occasions additional expense and difficulty, which may prevent its general adoption. A portion of the white lead is introduced into commerce, after drying, in the form of cakes, which are wrapped in paper, and carefully packed in casks, so as to avoid breaking them as much as possible. The handling of the cakes of white lead cannot be considered to be free from inconvenience, although unattended with danger, if due precaution be observed. In one manufactory in the Department of the Seine, the white lead is not potted as above mentioned. The soft paste is poured from the vats on to a cloth, in which it is wrapped, so as to form a square flat packet. Several of these packets, being arranged in alternate layers, with corresponding pieces of wood, are submitted to the action of a hydraulic press; and, by this means, the water is, in great part, expressed. The cakes are then uncovered, and cut into convenient shapes for the drying apparatus; from whence they are carried to the stove. A small portion of the products of this manufactory is sold in dry cakes; but the same care is not taken in packing these in casks as the conical cakes; for the product is disposed of to parties who are well aware that form is no indication of quality. The cakes are simply thrown into the cask, and packed by means of a cylinder, worked by a hydraulic press.

6th. Grinding and sifting the white lead preparatory to send ing it to market. —This second pulverization is generally effected by means of vertical mill-stones, revolving in horizontal troughs of the same material. The ground white lead is shovelled into a hopper, leading to a silk bolting cylinder, enclosed in a casing; at the bottom of which the white lead falls in the form of a fine powder. That portion which cannot pass through the silk, falls into a separate case; from which it is taken to be again passed through the mill. When the dust has ceased to fly, the sifted white lead is packed tightly in casks.

According to the above plan, the operations of pulverization, sifting, and packing, are evidently very injurious, by reason of the dust which flies about. The injurious influence may be much lessened by enclosing both the mill-stones and the bolter which receives the ground white lead immediately therefrom in an air-tight case. This has been done in one manufactory in the environs of Lille,— horizontal stones of white marble being substituted for the ordinary vertical stones. Each pair of stones is enclosed in a drum, furnished with a hopper above, in which the cakes of white lead are placed, and undergo a preliminary breaking by means of a striated cone, placed in its interior, and revolving on its axis. The fragments fall from thence into a hopper, fixed above the upper or running stone. The powder ground is thrown out by centrifugal force towards the periphery, where it is received by two openings and conducted to the bolter, which is in a lower chamber, and closed by a double door. In order to avoid the flying of dust during the packing in casks, the white lead is poured carefully into the cask, and packed by means of a pressing-screw, which works a cylindrical plate, a little smaller in diameter than the barrel, and presses it down upon the white lead.

7th. State of the white lead when gold in the market. —In the environs of Lille nearly the whole of the products of the white lead manufactories are sent out in powder or in cakes, viz., about two-thirds in powder and a third in cakes. A manufacturer in the Department of the Seine has set up in his establishment a complete workshop for grinding the white lead with oil; and nearly seven-eighths of his products are sold in the state of paste, containing from 7 to 9 per cent. of oil. In this manufactory the cakes of white lead are ground after desiccation in a mill similar in construction to a coffee-mill, and set in a closed chamber,— the white lead being first coarsely pulverized. When the dust has ceased to fly, the powder is to be poured gently into an iron cylinder, placed horizontally,—a small quantity of oil being added. The cylindrical vessel is then closed, and the mixture is effected by beaters, fixed upon a shaft, working longitudinally in the cylinder. A fresh quantity of oil is then added, if requisite; and the mixture then passes between two sets of cast-iron grinders, by which it is reduced to a very fine and homogeneous paste;— this paste is received in a vessel containing water, and is after wards put into casks for sale. Thus, when the white lead is to be ground up with oil by means of suitably-arranged apparatus, similar to that which we have seen at work, it need not be reduced to very fine powder and sifted; so that one of the most unhealthy of the operations is almost wholly abandoned, and replaced by another, which appears to be perfectly innocuous. It would therefore be very desirable that all the white lead, which, before it is used, must be reduced to paste with oil, should undergo that operation in the course of manufacture; and not in other workshops, where the workmen are exposed to saturnine diseases if suitable precaution be not observed.

It appears certain, from what was observed by one of us in a white lead manufactory at Birmingham, and according to the in formation which we have received from M. le Play, that the English manufactories sell the greater part of their products in the form of paste, which contains from 8 to 9 per cent. of oil. It would be very desirable to follow out this plan in France.

In most of the white lead manufactories great precautions are taken to preserve the health of the workmen. For instance, they are made, on leaving off work, to wash their hands, arms, and faces. For this purpose, there is a plentiful supply of water and soap, potters' earth, and, sometimes, vessels of water holding sulphuret of potassium in solution. In one of the manufactories in Paris sulphur baths are provided, in connection with the boiler of the engine. As regards the insalubrious portions of the work, the workmen are employed upon them alternately, and very rarely several successive days. A room is provided in some establishments, in which the workmen, on leaving off work, deposit their working dress; and, in almost all, the services of a medical man are provided at the expense of the principal. The workshops are in general spacious and airy, more especially those in which the white lead is ground and sifted. The walls and shafts of the machinery become covered with white lead, even when the grind ing apparatus is enclosed; which shews that the pulverizing process must still prove injurious.

From personal observation, and also from information which we have obtained, we are enabled to assert that the general condition of white lead manufactories is not at present so injurious to health as one might be led to imagine from the statistical accounts collected during the last ten years from the hospitals of Paris. There is besides very great difference, as regards salubrity, in the different manufactories which we visited. There was not a single one in which the old processes of manufacture had not undergone some improvement, and in some (we may cite in particular those of M. M. Lefebvre and Co., at Moulins-les-Lille, and of M. Besancon, of Ivry, near Paris) the improvements are very considerable and important. Even in these latter, however, further improvement would be very desirable.

For example, the operations of picking and scouring, and also the pulverization of the dry scales of white lead, have not been rendered perfectly innocuous; for this purpose it would only appear to be necessary to adopt the methods employed in England, and above described.

The manipulation in the process of potting, which, without being absolutely injurious to health, is not without inconvenience, besides causing useless expense, might be dispensed with, if purchasers could be dissuaded from attaching importance to the conical form of the blocks, which in reality it does not possess. If the whole of the white lead which is required to be ground up with oil could be sold in commerce in the form of paste, the in conveniences of reducing the cakes to powder, and packing the powdered white lead in casks, would be considerably lessened, as well as the causes of the maladies which are contracted in grind ing and preparing colors. The carrying of these ameliorations into practical effect does not appear to be attended with any difficulty; but their introduction into manufactories may be prevented, even against the will of the manufacturers themselves, by the prejudices of purchasers, who are wedded to old habits.

In conclusion, the following points seem to be established,— 1st. That the maladies to which the workmen in white lead manufactories are liable may be generally prevented by the substitution of mechanical processes for the manual operations, wherein the workmen are obliged to handle the white lead, as in the following instances: — By the employment of water in the separation of the scales from the residue of lead, and the pulverization and sifting of the scales of white lead. By the substitution of moulding in the form of prisms or bricks, in potting the white lead ground with water. By grinding with oil, by suitable apparatus, during the process of manufacture, such portions of white lead as require to be submitted to that operation before being employed. By enclosing in chambers separated from the workshops all the mechanism necessary for the pulverization and sifting of the white lead, when those operations are indispensably necessary. The dust might be prevented from passing through the openings necessary for the introduction of the materials, and for the working of the shafts of the machinery, by means of currents of air directed towards the interior of the chambers, which must be for that purpose surmounted by a pipe in the form of a chimney, rising above the roof; and also by causing the shafts to work in elastic bearings, or in stuffing-boxes kept constantly lubricated. Lastly, these precautions might be completed by a perfect ventilation of the workshops and hygienic precautions which may be readily observed by the workmen. 2nd. That although many ameliorations favorable to health, recently introduced into most of our white lead manufactories, have consider ably reduced the amount of sickness, there is yet much to be desired, especially as regards the separation of the scales of white lead from the metal, pulverization, and sifting, which precede the grinding with water.

As the commission with which we were charged by the Academy was simply to examine in what respects the white lead manufacture affected the health of the workman,—the casualties therefore resulting from the employment of this substance in the various arts, and the means of preventing them, although of great importance, has formed no part of our enquiry.

With respect to the manufacture itself, your commissioners are of opinion that very important improvements have been effected in relation to the health of the workmen, and that this will cease to be an unhealthy occupation, when it shall be carried on by the improved methods and with the precautions pointed out in this report.