Dictionarium polygraphicum. Of compounded colours for washing of maps.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
A blue to wash upon paper.
Take half an ounce of the best azure, of kermes, one ounce; mix them and temper them with gum-water, and it will be a glorious blue.

A Venice blue.
Make quick-lime into a paste with strong vinegar, and half an hour after, put more vinegar to soften it, then add to it an ounce of indigo finely powdered; mix them together and digest them for a month or 6 weeks, in horse-dung.

Another excellent blue.
Mix fine chalk with juice of elder-berries, full ripe; and put to it a little alum-water.
Ultramarine, blue, bice, smalt and verditer, ground singly with gum-water, or together, make a good blue.

To make blue smalt.
Take fluxible sand, sal-nitre, and cobalt, and mix them together.

Green, digest filings of copper in distill'd vinegar, till the vinegar is blue; set it in the sun, or on a slow fire, till it is thick enough, and it will be a good green.

Or thus; take cedar-green, which is the best of all, or instead of that, green bice, steep it in vinegar and strain it, then grind it well with fair water, and add to it a little honey, and dry it well, and when you use it, mix it with gum-water.

A light green; grind together juice of rue, verdegrease, and saffron, and use them with gum-water.

Or thus; steep sap-green, flower-de-luce, or tawney-green, in water; also verditer and ceruse, mixt with a little copper-green, make a good light colour.

A never-fading green.
Put the juice of flower-de-luce into gum-water, and dry it in the sun.

To make a lively yellow dissolve orpiment in gum-water, put to it a little ground vermilion; grind them together, and they will be a very lively colour.

Orange-colour; red-lead and yellow-berries make a good orange-colour: or thus; boil an ounce of arnotto, and a drams of pot-ashes, in a quart of water, till half is boiled away; then strain it and use it hot.
This is good for paper, parchment, vellum, white leather, quills, &e.

Flesh-colour.
Mix white Indian-lake, and red-lead, (according as you would have it, light or deep) and to distinguish a man's flesh from a woman's, mingle a little oker with it.

Brown.
Ceruse, red-lead and English-oker, and path, make a good brown.

Spanish-brown.
This not being calcin'd, is a dirty colour; but yet is proper for a horse, dog, &e. but to shadow vermilion, or to lay upon any dark ground, behind a picture, or to shade berries in the darkest places, or to colour wooden posts, wainscot, trees, &c. (being burnt) is very good.

Dictionarium polygraphicum. Ultramarine.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
ULTRAMARINE is a rich and beautiful blue used by Painters from an azure stone commonly call'd Lapis Lazuli, which is an opaque stone of a fine sky-colour or Turkish blue; or like the blue flowers that grow in corn-fields; it is embelhsh'd with small streaks and sparkles of a gold colour.

This stone comes from Persia and the East-Indies, and as some say from Africa; but if from the last, it is in no great quantities.

There is also a kind of lapis lazuli found in Germany and Hungary; but not fix'd, tho' as hard as that from Asia, which they call Lesurstein and its colour Asurbleau; but its colour changes in sometime, and becomes greenish: however it is used by Painites.

The best Lapis Lazuli is that which is fix'd; that is, can endure the fire without altering colour.

Before you proceed to extract your ultramarine, take some account of the manner, to know whether the stone be good, for unless it is singularly so, you'll lose your labour: put pieces thereof on live coals, and blow them continually for an hour; if they retain their first hardness and colour afterwards, you may conclude them good; but if they crumble between your fingers, they are naught. It may be tried otherwise in an iron-ladle put into a furnace with some of the stone to heat, and so quench it in strong vinegar; if the colour remains still unchang'd and splendid, you may assure your self 'tis good.

When you have made this tryal, calcine it, which to do the easier, break the stone to pieces, as small as hazle-nuts, wash them afterwards in warm water, and set them in a crucible, on a windfurnace, or into an iron-ladle to reunite; then cast them into a glaz'd earthen vessel of distill'd vinegar to quench them in; do thus seven times, to prepare them by calcination for powdering, and to prevent their sticking to the mortar.

Thus calcin'd, dry them well, and so powder them in a stone-mortar well cover'd, and accordingly scarce it with the same caution, as perfumers do their most delicate and finest powders, lest the best should go off, and dispel it self in the air: and thus preserve this precious powder with all imaginable care.

Some derive its name Ultramarine of the Latin ultra beyond and marinus of or belonging to the sea; a.d. beyond-sea, because first brought into Europe from India and Persia.

It is the common opinion, that the method of making it was first discover'd in England by a member of the East-India company; who having a quarrel with his associates, made the secret publick to be reveng'd of them.



To make a liquid for moistning and grinding tht powder withal, &c.

For moistning and grinding your aforesaid powder of the stone, take a pound and a half of running warer, and put this into a new earthen pot, add to it an egg-shell full of raw honey, boil it until it have no more scum; take the pot off, and keep this hydromel, or liquid for use in bottles, as we shall give occasion sbr hereafter.

This done, take four scruples of the best gum dragon, grind it on your marble, with some of the hydromel, and then put it into a glass; add thereto as much hydromel as you find con venient to bring it to a violet-colour, so cover it, and preserve it for use. This liquid is good for your powder of lapis lazuli; if the colour be too violet, add the less hereof; if otherwise, the more, as your judgment, or experience shall direct.

Put half a pound df powder at a time into a small porphyry, or marble vessel, the larger the mortar the worse, for you'll lose more, and be longer a grinding; pour leisurely by little and little thereon, some of your violet liquid, grind these together for a full Hour, still wetting it; you may use three or four ounces of liquid to the half pound of powder, and you'll have it very good; you must take care of grinding it tdo long, for then it will lose its colour.

When 'tis thus ground, dry it on a marble or flat stone, where the sun does not come at all, cover it well to preserve it from dust; when 'tis dry, 'twill powder easily between your fingers, if it be rightly done; if so, let it alone on the marble, but if it be clammy, or stick, take it off, for it has still some unctuosity of the honey in it, which must be cleansed away by a cement.

Your lapis being thus dry, wash it well before you put it to the cement, for which you must use a glaz'd earthen bason round above like a barber's, and well glaz'd within; put your lapis therein, and pour thereon some of the mild lixivium hereafter mention'd, as much as will rise above the surface four inches; wash the lapis very well with your hands, and then let it settle, and 'twill precipitate. The liquid being clear'd again, decant it into a large copper, or earthen vessel, then let the lapis dry in a shade in the same vessel it was wash'd in, and spread it afterwards on the flat marble, or porphyry, and there let it lie until quite dry: thus it is prepard for mixing with the cement, of which we will give the preparation hereafter .



To prepare a mild and a strong Lixivium for the Lapis Lazuli.

To make these lixiviums, take ten handfuls of vine-stalk ashes well scare'd; put this into a large vessel that will hold thirty pound of water, with a faucet at bottom; press the ashes very well, and put to them twenty pound of warm water. When it is funk to the bottom, open the faucet, so as it may only drop into an earthen vessel; when it is all come out, stop the hole, and strain this lixivium through a felt strainer, and so keep it in a glass, or glaz'd pot well cover'd: this is the strong lixivium.

Again, pour in on the sime ashes, the like quantity of warm water, and do as before; so you'll have an indifferent strong lixivium, which keep as the former.

Do this a third time, and you'll have the mild lixivium mention'd in the preceding page.

These three are very useful both for moistning, and to draw the powder of lapis lazuli from the cement; wherewith it must be mix'd, as will be shewn anon: which separation being sometimes hard to perform, we are oblig'd to have recourse to these varieties of lixivium: stronger, or weaker, as we find them convenient for the purpose.

You may yet make another lixivium to take away the greasiness of the cement thus; boil calx of tartar, as much as you please, in clean water, for about a quarter of an hour, and keep u for use as the former. This is excellent for washing the lapis lazuli with; it strengthens and improves the colour thereof.



The form of the glasses for preserving the liquids in, which are employ'd on the Lapis Lazuli.

There always remains some of your colour in the waters, or lixivium, wherein the lapis lazuli is prepar'd throughout all the process; you must therefore have a very large vessel of brass, or earthen ware, glaz'd and polish'd very well at bottom, wherein must be three holes; one in the middle of the side, the next a little lower, and the last about two inches from the bottom; stop these holes without side very close, to prevent leakage.

Then pour all your waters into this; though you then perceive no colour ar all, yet after ten days you'll have it at bottom, whither it will descend gently; and to get it you must go artificially to work, first opening the first cock or hole, andletout the water above that, before you open the other two; and thus yon may get the colour without muddying, or lofing any by the waters, which mix with the rest.


To make strong cement to mix with Lapis Lazuli, to separate the finer and better stuff from the other.

One cannot so easily part the finer lapis lazuli from its grosser pans, without making use of this cement to unbind the parts: take four ounces of very pure and clear Venice-turpentine; six ounces of rosin of the pine, six ounces of Grecian pitch, three' ounces of very good mastich, three ounces of fresh wax, an ounce and half or linseed-oil cleansed, as ill all be directed.

Put the turpentine into a new-glaz'd earthen pot very clean, to dissolve over a flow charcoal fire, and continue stirring it with a wooden spatula, throw into this by degrees, the rosin of the pine, in small pieces, and stir it still very well; thus put in successively the pitch, the mastick in powder, and last of all the wax sliced small, stirring all continually about to mix and incorporate. Take great care of your fire, lest the cement should blaze, or burn, all the ingredients being hot of themselves, and combustible. Having well incorporated them, pour in the linseed-oil, stirring it as before, and so let it boil gently for a quarter of an hour.

To try whether the cement be enough, drop some of it osf the spatula into a vessel of cold water: if it spread, 'tis not enough; but if it do not, 'tis sufficiently boil'd; so take it off. Or else you may wet your fingers, and take a drop thereof, roll and draw it out in length; if it snaps and breaks of it self, 'tis a sign that 'tis enough: take it off, and pour it boiling hot into an hypocras-bag steeped before in hot water; take care to let it go all through into a vessel of cold water, and for the better se curity, squeeze it along from top to bottom with two flat sticks, that none may remain in your bag. Afterwards work it well with your hands, till all the water be drained from it, and because being hot it may stick to your fingers, you may anoint them with some of the linseed-oil.

The cement being thus prepared, keep it in a vessel of cold water, shifting your water every day, or every second day; and by this method you may keep itfor ten years.


To make a weaker Cement for separating the colours of Lapis Lazuli.

This second cement, which is the softer and milder, ought to be first employ'd on the powder of lapis lazuli; it draws the colour much quicker and better than the strong cement, which ought not to be used till after the milder; the whole se cret of separating the colours, consisting in ufing the cements; for without a due care hereof, it cannot be done perfectly.

To make this cement, you must take four ounces of very pure turpentine, four ounces of rosin of pine, six ounces of Grecian pitch, one ounce of fresh wax, six drams of linseed-oil, purified, mix and incorporate them successively as before. Ob serve only, that this is sooner done than the former, because 'tis weaker, and will give the colour soonest; therefore you must manage accordingly.



To purify Linseed-Oil.

The use we have for linseed-oil in our cement, obliges us to give this preparation, and way of purifying it, whereby it is made more fit for our purpose.

Take good and clear linseed oil, of the colour of saffron, and put it into a glass, shap'd like an ox-horn, with an hole at bottom to let out the water, which you must mix with the oil, letting them settle until the oil rises all uppermost; then open the hole, and let the water out, and the oil remain behind. Then shake the oil again, with more fresh water, let it settle, and the water run out as before; do thus eight or ten times, till the water comes out as clear as it went in, and so the oil will be pure and fit for your use; keep it well stopt in a glass bottle. If you can't get linseed-oil, you may use oil of bitter-almonds, without purifying, for it needs none; but take notice, the linseed oil is belt or any, though cheaper than the other.



How to incorporate the powder of Lapis Lazuli with the strong, or weaker cement.

We have already given the way to prepare the powder for mixing with the cement, to extract the colours; we now come to shew how to mix it with the cement, in order to extract the ultramarhe from them for painting.

Take a pound of the powder, and the like quantity of cement assign'd before, observing always to take the first that was work'd with the hands; cut the cement small, and the pieces being a little wet, put them into a glaz'd earthen pot, over a fire of red-hot ashes, to melt, and take care it does not boil; if it should, you must prevent the damage which it might cause, by putting in some linseed-oil. The cement being thus melted, anoint all your spatula over, from the handle downwards with the same oil, and so put in the powder by very little quantities, and taking a great deal of time, that they may the better incorporate; and be sure to stir it all the while very well with the spatula, so as to make it all alike, until it become like an ointment or salve: then off with the pot, and throw the stuff boiling hot into an earthen-bason of cold water, and at that very instant take off all that sticks to the sides of the pot. When it is cold enough to be handled, if it appears well colour'd, it is a sign you have work'd it well: this done, rub your hand with linseed-oil, and work it as they do a paste of bread or dough, for one hour, that it may be throughly compact. The longer you work it, the better and easier the colour may be drawn; afterwards make it up like a loaf or brick, and set it in an earthen dish to dry, pouring thereon some fresh water; let it steep for fifteen days, the longer the bettef for extracting the ultramarine.



To extract the Ultramarine.

Take therefore the loaf of cement and powder, washing it in the same water extraordinary well with your hands; weigh it to know the quantity of oil it requires, and put it into an earthen bowl or dim, very smoothly glaz'd, rubbing first the bottom with your linseed oil; then pour in water scarce warm'd, until it arise two inches above the matter; let it stand in this condition a full quarter of an hour (or less in the spring-time;) pour this water afterwards into the vessel before mention'd, adding more warm water to your matter, and so it will soften: continue thus whilst there remains any tincture thereon; by this means all the substance that is good for any thing, will be se parated from the cement, which cannot be done otherwise.

Whilst it is imbib'd in the warm water, you must move and rowl it gently round with two sticks, or spatula's of box, or any other well polish'd wood, rounded ac the ends smooth like a wallnut; let them be about an ell long, and an inch thick. When ever you perceive the matter stict to the bottom of your disj, rub your hands with linseed-oil, and stir it about leisurely so as to colour the water, which you must put along with the former, in the mean time holding up the matter with your staves, lest it should stick to the vessel.

Take notice that a little steeping at first will tinge the water very much, and when the cement is just yielding its colour, it will discover certain bluish streaks on the water like the sun's-rays, and then you must strain this water out among the other, through a scarce, that the grosser part of the cement may remain; afterwards pour in by little and little the fresh warm water, stirring the cement easily, that it may not dilate too much, and give its colour all at once. After you have thus stirr'd it about five or six times, close and amass it anew, by which means you'll see how much it is diminish'd, and what quantity of colour it has given.

If the lapis be good and right, you'll find the first steepings, yield about four or five ounces of ultramarine, which keep apart by its self as the best and finest colour, though it appear grosser than the others of this sort, by reason of the gold-colour'd veins, which are peculiarly therein.

For the second, whereof you'll have three or four ounces, you must follow the processes aforementioned: this indeed will be finer than the other, but not so good a colour; keep it also by itself.

Draw off a third, and this will b e still finer than the former, but paler, and more bright coloured. You must still pursue the same Directions to extract it, letting your Water be but half lukewarm, and take care to manage the cement dextroufly with the spatula's, and so preserve the colour apart.

You may extract a fourth colour after th'u rate, but the wa fer must be hotter, and you must press the cement very well with the spatula's to squeete out the colour; and if meer water will not do, make use of the mild lixivium. This last colour will be greyish orash-colour'd, and of no great value, and therefore not at all to be mix'd with any of the rest.

Observe here that you can't take up less than eight hours full, to extract the colours, nor less than ten or twelve to allow the water for settling; and if you perceive the colour does not come out free enough with the warm water, add a third part of our mild lixivium, and if that does not do, use all lixivium, but let it be cold; and when that fails too of effecting it sufficiently, you must make a lixivium of vine.stalk ashes, and this being strain'd, let it boil for half a quarter of an hour, until it be sharp enough to bite your tongue; and then let it settle and grow clear; this is your last shift for extracting your colour, and with this heated, walli your cement very well, and set it aside. The whole design of all this trouble, is only to serve for obtaining the greater quantity of ultramarine, and this consists in the goodness of the lapis lazuli and the cement, which the circumspection and care taken in all their preparations must advance.



The method of cleansing the Ultramarine when it it separated from the cement.

After you have extracted all your colours out of the cement, »nd the water quite settled and separated from them, pour on some of the mild lixivium before prescribed, and so wash them with your hands, (but don't rub it between them) thus you'll fake away all the grease of the cement; afterwards wash it three or four times in fair water, and ler me waters settle well before you put them into their proper vessels.

You may else another way purge the ultramarine thus: take the yolks of pullers-eggs, that have been sed only with corn, and not with greens; prick these with a pin, and so moisten the colours, kneading the mass with yqur hands, and washing it afterwards with your mild lixivium, until the lixivium falls oft clear again. This done, wash them three or four times over with fair water, letting the waters settle well before you put them into their vessels.

This last way of purifying the ultramarine, is mighty effectual; but here is another help to be used with it, which is a very great secret, and performed thus: After the Colours are quite washed according to former directions, as well as possible, you must cast therein by little and little, a bull's-gall, rubbing it by degrees with your hands; so wash them often in dear water, and you'll have the colour in full perfection.



To strain off' the Ultramarine already wash'd and purified.

It is necessary to strain off the ultramarine, and the rest of the colours, that if any grease, or unctuosity of the cement remain, it may be taken quite away, for these colours require a perfect and extraordinary purification.

For this purpose take a fine searce, and pour thereon the last waters, with which you washed the ultramarine, and so strain them afterwards through another fine searce, and a third time through red quintain or crape; but you must observe when you strain them, to let them stand 'till you perceive them limpid and clear, and so soak off the water dextrously with a spunge, and be sure not to strain them promiscuously all together.

This being done to all the waters, let your colours settle in their proper vessels, and dry in the shade; when dry, put them into little leather bags; tie these close, rubbing them and pres? sing them with your hands: this will make them very subtile, and when the bags are opened, they'll shew much fairer than before.



To correct the colour just before prepared.

Few persons, unless such as are very curious of their work, make any use hereof, because of the time it takes up, tho' it would turn very much to their account; for one ounce of this colour corrected, will go farther than three that are not.

If you would make your colours just before prepared, much finer and effectual than they are, mix them again with a strong cement, and let them remain therein for three days; afterwards proceed according to the last directions, to separate them again; reiterate this over again, and you'll have them exceeding good; and tho' they diminish somewhat in weight, yet that loss will be repaid considerably in the beauty and value.




Another way to make Ultramarine, and draw off the colours with more expedition.

This method of making ultramarine is much more ready than the former; and experience will shew whether the colour be a gainer or loser thereby.

Take a pound of lapis lazuli, calcine it in a crucible, and quench it afterwards in vinegar, so let it dry, and then reduce it to a very fine powder; grind it on a porphyry with fair water, and set in a glazed earthen vessel in the shade, until it be dry; if you find it coagulated all in a mass, you must powder it again.

This done, make a cement of three ounces of Grecian pitch, four ounces of rosin of the pine, three ounces of mastich, three ounces of frankincense, two ounces of oil-olive; set these over a slow fire in a small earthen pot, into which pour first the oil, and when that's hot, put in the rosin, then the pitch, then the incense, and last of all the mastich, stirring them continually with the wooden spatula, and let them boil a little.

Having made the cement, get another earthen vessel, and put thereinto the lapis lazuli, and pour on it the cement hot, stirring the whole together with the spatula very leisurely, until they perfectly incorporate; let this stand a whole day, and when you would draw off the colours, pour thereon boiling water, stirring it very smartly.

When it begins to cool, pour it out, and so put in more hot water; do thus 'till the warer begins to draw off the colour, and so continue until it be quite extracted; you may distinguish the waters, and so set them apart, and obtain the variety of colour as in the former way.

If your colour seems to be clammy or nasty, you may cor rect it thus: aid thereto tartar dissolved in water, as much as will drown it, and let it repose for one day at least, so wash it in warm water, and you will by that means have it very correct, and well-purified.



Another way to make Ultramarine.

Granting the two former ways to be sufficient, we will how ever here give a third, which we believe may as well be pleafing to those, who are not satssfied with the other, as to such per sons as have a curiosity for these sorts of work; and thus we pro pose to procee'd.

You must break the lapis into gross pieces, as small as nuts, then set these in a crucible into the furnace, till they redden with heat, and so cast them into cold water; do thus six or seven times, and so reduce them to impalpable powder in a porphyrymortar well covered over, lest the powder, which is very subtile, should disperse away into the air, and then scarce it with a fine scarce also' covered.

After this, take rosin of pines, ordinary black pitch, mashch, fresh wax, and turpentine, of each three ounces; of incense and linseed-oil, each one ounce; melt all together in an earthen vessel, stirring them very well, 'that they may mix; this stuff being well incorporated, cast it into water, and keep it for use.

To each pound of lapis lazuli add ten ounces thereof, and set them to dissolve in a pot over a small fire, first melting the cement, and then casting on the lapis lazuli 'by little and little, observing such an order in this, and continually stirring the mass with a stick, that they may mix insensibly together. Afterwards cast the mass into an earthen vessel of cold water, and anointing your hands with linseed-oil, mould it up into a number of cakes, or rolls, which leave in cold water for five days, shifting the water every other day.

This done, put them into a large and very clean glazed earthen vessel, pouringon them some clean hot water; when that cools, pour in more hot, and do thus 'till the pastils soften with the heat of the water: this done, put them into hot water, and let them be until it receive a bluish colour. Strain this water to receive the grosser pieces, and so put it into another glazed earthen vessel very clean, adding more to the pastils, which strain through a fine searce afterwards among the former; continue this until all the colour be extracted, and no more remain behind.

Your water must be only warm, otherwise it will occasion a blackness in the colour, which is to be taken care of, and imports very much.

All the coloured waters being in the vessel, you may cleanse them of any unctuosity, by repofing them for twenty-four hours, in which time the colour will stick to the bottom; then you may pour off the water gently into another vessel, and it will carry oft the grease along with it; strain it afterwards into the veslel, where the colour is again, through a fine searce, and all the grease and nastiness will be left behind. Do thus thrice, stirring the colour very well every time you return the water to it, that the filth and grease may ascend from it, and it will always stay in straining on the searce behind the water.

This done, let the colour precipitate entirely, and so pour off all the water very leisurely, for rear of disturbing it; dry this colour, and you'll have delicate ultramarine.

If you would imitate this colour at little charge, make use of our blue enamel, after the same manner; and instead of the lapis lazuli, observing without exception the like regimen and prescription just now delivered in every respect, and by this means you'll have a very pretty agreeable colour to paint with, and for tinging of glass.

This blue is qne of the richest and most valuable colours used in painting.

Those, who prepare it, make usually four sorts, which procur'd by so many different lotions, or washings.

There is ultramarine of the first sort sold for 11 l. sterling an ounce, and of the last for about twelve or fifteen shillings.

Ultramarine must be chosen of an high colour, and well-ground, which may be known by putting it between the teeth, and if it seel gritty, it is a sign it has not been well-ground.

To know whether it be pure and unmix'd, put a little of it into a crucible, and so heat it red-hot; and if the powder has not chang'd its colour after this trial, it is certainly pure; on the contrary, if there be any change, or any black specks in it, then it has. been adulterated.

Besides this, there is another sort call'd common, or Dutch ultramarine, which is only lapis, or smalt well-ground and pulveriz'd; the colour of which, when used by the painters, is much like that of true ultramarine, tho' much less valued.



To make Ultramarine.

Pour five ounces ot linseed-oil into an earthen dish, with three or sour drops of water, set it on the fire, and let it stand 'till it begins to fry or boil; and then put in half a poundof white Virgin wax, broken into small bits. When the wax is melted, put in half a pound of Greek pitch, and two ounces of powder of mastich, which has been before melted by itself, and also an ounce of turpentine; let all together stand over the fire to melt for aa hour.

Afterwards pour this composition into cold water, and if it proves soft like butter, it is enough; but if you seel any hard grains or grit, conclude that the majlich has not been melted enough, therefore set it over the fire again.

When the whole is brought to a due temper; put blue lapis into a crucible, and set it into the fire 'till it is red-hot, like the tire itself, and then throw it into white-wine vinegar; which it will imbibe, or absorb, 'till it bursts and breaks into small bits. Pound these bits in a mortar, and then incorporate this powder with a little of the above-mentioned composition; but with as little, as possibly may be, and let it remain in this state for about fourteen or fifteen days.

This being done, lay a board a little inclin'd upon the edge of a table (which board, if it had a channel or trench cut along it, would be more convenient) and under the foot of this board place a glass vessel or receiver, and put the blue paste at the upper part of it, and a vessel of water over that, so that it may distil drop by drop upon the paste.

Having dispos'd all things in this manner, help the water to dilute the paste, by stirring it very gently with the small endof a smooth stick.

The first blue, which will come away drop by drop, will prove the finest; and when you perceive that it begins to lose part of its beauty, change the vessel that receives it, and this will be a second blue; and you may likewise by thus changing the receiver have a third sort, which you may use.

Set these three sorts of ultramarine to dry, then put them up separately in bags of white leather.




Another way of making Ultramarine.

Take a quarter of a pound of lapis lazuli, and lay it upon burning coals, letting it lie 'till it is red-hot, and then quench it in very strong vinegar.

After this has been done, grind upon a hard marble stone with rectified brandy; the more it is ground, the finer the ultramarine will be. When it has been thoroughly ground, leave it upon the marble, or you may put it up in a vessel, while you prepare a paste, or pastel, for the incorporating the lapis with.

In order to make this paste, take two ounces of yellow wax, two ounces of turpentine, as much rosin, and as much linseed-oil; melt all these together over a flow fire, 'till they begin to bubble, which when it does, it is enough.

Pour this melted composition into glax'd pans, and it will be your ultramarine pastel or paste, of which take a quantity proportionable to that of the lapis, that has been prepar'd, and knead them together upon the marble stone, i. e. both the lapis and pastel together, which when they have been incorporated, leave them in that state for a night.

Then in order to force the ultramarine out of the pastel, pour fair water upon it, and knead it with your hands like a piece of dough, and the ultramarine will squeeze out, which is to be receiv d into an earthen vessel set under your hands; then leave it to settle in the said water, 'till you perceive the ultramarine has funk to the bottom.


Another way.
Take linseed-oil, new wax, and arganson, of each two ounces; rosin, and mastich in tears, of each half an ounce; Burgundy pitch two ounces; incense of frankincense one drachm, of dragon's-blood the same quantity; let each of these ingredients be bruised in a mortar by themselves; then set the linseed-oil over the fire in a pan, and when it begins to fry, put in the ingredients one after another, letting the dragon's-blood be put in last; stirring the others continually with a stick, or spatula, anci when you perceive the composition to become glutinous and stringy to your fingers, the paste is fit for use.

Then having prepar'd the lapis lazuli, by burning it on a coalfire, quenching it in white-wine vinegar, grinding it very fine upon a marble, and searcing it through a fine searce; incorporate it with your paste, and let it remain in that state for twentyfour hours, and then force out the ultramarine with spring-water, but be sure not to use any other water, and you will have the first tincture, or degree of blue, which will be the finest and most lively'of all: repeat this to the third time, and if after all the remains be put into a chymical vessel, you may get out the gold with which the lapis was impregnated.

Some persons knead the paste at once in a vessel of milk-warm water, into which they squeeze the ultramarine, leaving it to settle for twenty-four hours or more, and then pour off the water by inclination, and find the ultramarine at the bottom, which they set to dry in the sun.

Some leave the lapis incorporated in the paste for the space of a month, before they squeeze out the ultramarine; and in the paste put only oil of turpentine, instead of linseed-oil and turpentine; and black pitch instead of Burgundy pitch: and as for the lapis itself, they heat it, quench it, grind it, and scarce kin the manner before directed.

Dictionarium polygraphicum. Of dying Violet and Purple colours.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
1. To make a purple dye.
Take water q. s. alum twenty ounces, madder five ounces; boil, enter twenty yards of stuff, and boil it two hours and an half; take it out, and wash it well; wash the lead, and then put in clean water a sufficient quantity, logwood ground two pounds, boil it a while, and enter your cloth, handle it well, and take it out and cool it; enter it again, and put it in and out 'till the colour is strong enough.

2. To make a Violet colour in grain out of a sad Blue.
Take fair water, clear bran-liquor, of each equal parts, a sufficient quantity; alum nine pounds and an half, tartar five pounds and an half; melt them, and enter thirty pounds weight of wool, yarn, stuffs cloth, &c. of a sad blue colour: boil four hours, cool, wash it in cold water. Take fresh bran-liquor a sufficient quantity, cochineal, tartar, both in fine powder, of each fifteen ounces; mix, enter your cloth, handle it to a good heat, boil it two hours, handle it well, take it out and wash it, and it will be a pure violet or purple colour.

3. Another purple colour without bluing.
Take clear stale wheat bran-liquor, or sour tapwort, a sufficient quantity; alum three pounds, enter twenty yards of broadcloth, boil it three hours, cool and wash it well. Take fresh bran-liquor a sufficient quantity, madder twenty ounces, enter your cloth, boil with a quick fire, cool and wash. Take clear or fair water a sufficient quantity, logwood ground twenty-four pounds, boil half an hour, and put in some urine; then enter your cloth, and handle it, and boil half an hour; take it out and cool it, add nut-galls bruised two ounces, and enter your cloth again, handle it, and boil it half an hour, cool and wash it.

4. Another Violet or purple colour.
Take clear stale bran-liquor a sufficient quantity, alum three pounds, enter twenty yards of broadcloth, and boil two hours and an half; cool and wash well. Take fresh liquor a sufficient quantity, madder twenty ounces, enter your cloth, and boil with a quick fire, cool and wash well. Take fair water a sufficient quantity, logwood ground eight ounces, Brasil ground two ounces; let them boil a quarter of an hour, enter your cloth at a boiling heat, handle it, and boil a quarter of an hour; take it our, and cool it; add urine a sufficient quantity; enter your cloth again, boil a quarter of an hour, then cool and wash it well.

5. A good Violet or purple colour.
Take water four gallons, myrtle-berries eight pounds, alum ten ounces, calcined brass one ounce, mix them in a brass kettle or vessel, boil half an hour, and strain it.

6. Another purple colour.
Take orchal, mix it with half urine, and let it boil 'till it is of a dark colour; then put in the matter you would dye, letting it lie twenty-fours or more.

7. An excellent Violet colour.
Take calcin'd tartar, turnsole, of each a pound, beat them and tye them up in a linnen-cloth, and steep them twenty-four hours in water, and then put in the matter, which you would have to be of a violet colour.



To dye stuffs, &c. of a beautiful Violet colour.
Alum the stuffs with half a pound of alum, two ounces of tartar, and a handful of madder in clear rainwater made hot, for every pound of stuff; let these ingredients be stirred well together, and when they are dissoiv'd and begin to boil, put in the stuffs to be dyed, boil them for half an hour, take them our, let them cool, and rinse them out.
Put fresh water to the liquor, and put in a quarter of a pound of brown wood in a clean bag, boil it for an hour and an half, and then put in the goods again, and boil it for an hour and an half; then tike it out, and put into the hor suds a quarter of a pound of verdegrease, it being first dissiilv'd in warm water. Stir it well about, and then put in the stuff; again, stirring it about for a quarter of an hour, 'till it begins to boil; then take it out, cool and rinse it, and it will be of the most beautiful violet colour.


Another.
Having alumed the ware as usual with one half starch-water, allowing for every pound two ounces of alum, and an ounce of tartar; boil them together for an hour: then having hung other fresh water over the fire, when it is hot, for every pound of ware put in two ounces and an half of Brasil shavings, and a sufficient quantity of great pot-ashes; boil them together for a quarter of an hour, and then put in the stuffs, and there keep them 'till they take the dye; then cool them, and rinse them out.


To dye Thread of a lasting Violet colour.
Boil half a pound of tartar; half a pound of alum, two ounces of Brasil wood, and half an ounce of salt-petre together, then lay the thread four hours in the liquor; then rinse it out, and dry it. Then brown it as follows;
Boil a pound of brown wood, and half a pound of Brasil in a large vessel; and use the dye in the following manner:
Divide it into four equal parts; remembring that each part is to be used warm, and the thread dyed after each operation; and when the first part is us'd, let there be added to it half an ounce of sumach, and one drachm of salt-petre.
The second time, a quarter of an ounce of calcin'd tartar, and one drachm of verdegrease powdered.
The third time, a quarter of an ounce of sumach, and one drachm of salt-petre.
The fourth and last time, if the thread remains a little reddish, pour in a quart of hot sharp lye, and you will find the thread of a beautiful violet brown.
But if the thread be boiled in alum, and blued with woad, and then browned with Brasil, the colour will be more beautiful and lasting.


To dye a good crimson Violet.
First dye the stuff a deep blue green, and boil it as for right crimson, rinse it very clean out of the suds, and finish it with three drachms of cochineal, in proportion to one pound of ware, and you will have a right good colour.

A brown Violet colour.
For twenty-five yards of fustian, frize, or other goods, take three quarters of a pound of alum, half a pound of tartar, half an ounce of sal-armoniac, boil the stuff in this liquor for two hours, rinse it out in clean water, and dry it in order to blue it, as follows.

The Blue dye.
Dye it a deep lasting blue with woad or indigo, then rinse it clean and dry it.

The brown Violet.
Boil a pound of Brasil in a large pot by itself, and divide it into four equal parts; then with a clean ladle, put one part into the kettle before you put in the stuff, and also salt-petre and sal armoniac pulveriz'd, of each one drachm; after this pass the stuff very well through the dye, then dry it, and put in another part of the Brasil, and add a quarter of an ounce of powdered galls; then pass the stuff through the dye again, and dry it again; thus repeating the operation twice or oftener; and after the fourth time, you will find it of a beautiful violet colour. But you ought to remember, that the fourth time you must use a clean sharp lye, in order to brighten the lustre, adding to it one drachm of calcin'd alum.
This colour may be produe'd from brown wood, and a quarrer of a pound of Brasil in four or five operations, and by adding galls twice, but it is not so durable as the other; but in order to render it more lasting, you may add more brown movd and indigo, and may in the last place brown it with Brasil.

To dye silk of a Violet colour.
For every pound of silk, take one pound of blue, or Provence wood, boil and stir the silk in it, as in the red dye; put into the last suds a few galls, then rinse the silk and dry it.

A good lasting Violet.
To every pound of silk take one pound ot galls, and one pound of blue wood; and put in the silk when the suds are cold, for the colder the suds, the bluer the violet colour will be, which must always be bluer than the tawneys: let it lie a night in the sods, then in the morning rinse and dry it.
From the following dye are compos'd the best tawnies grey and crimson goat-colours.

To dye silk a Violet brown.
Let the silks be alumed as for tawney; and to every pound of silk, take two pound of Provence wood, boil it in a bag for a full hour; then take it our, put in the silk, boil that for an hour, and then take it out, and put in the bag again; then rinse it in a lye, as is directed to be made for other colours, and with out bole-armoniac, and after that in running water.



Crimson violet.
The manner of dying silk a purple.
First boil and alum the silk as for madder-red; then put a sufficient quantity of clean water into a clean kettle, and for every pound of silk take an ounce of galls, and an ounce and an half of cochineal tedue'd to a fine powder, one ounce of;mh, boil them together as you do the crimson; then lay the silk to soak in it for one night, afeer which cleanse it, and you have a good purple.

Dictionarium polygraphicum. Vermilion.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Vermilion is a very bright beautiful red colour, in great esteem among the ancients under the name of minium.

There are two kinds of it, the one natural, and the other factitious.

The natural is found in some silver mines in the form of a ruddy sand, which is afterwards prepar'd and purified by several lotions and coctions.

The artificial is made of mineral cinnabar, ground up with aqua-vita and urine, and afterwards dried.

It is also made of lead burnt and wash'd, or of ceruss prepar'd by fire: but this is not properly call'd vermilion, but red-lead.

Yet this last, however, seems to be the real vermilion of the ancients, and both apothecaries and painters still give it the name to enhance the price.

We have two kinds of vermilion from Holland, the one of a deep red, the other pale; but 'tis the same stuff at the bottom: the only difference of colour, proceeding from the cinnabar's being more or less ground: when the cinnabar is finely ground, the vermilion is pale; and this is preserv'd before that, which is coarser and redder.

It is of very great use with painters in oil and miniature; and among the ladies for a fucus, or paint, to heighten the complexion of such as are too pale.

Vermilion some disapprove of, to be us'd in painting prints, unless it be prepared by washing, as is directed for minium; and then chiefly for dry painting, except it be by those persons, who can use it moderately, and with judgment; for all heavy colours will drown the shades or strokes of the engraver.

Dictionarium polygraphicum. Verdeter, verditer, verditure.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Verdeter, verditer, verditure is properly a native mineral substance, of a stony consistence, and of a blue colour, but spangled with little shining points like gems; it is found in the mountains of Hungary and Moravia, and is the same that is also call'd lapis Armenius.

The green us'd by the painters, and call'd verditer, should be made of this stone well-ground and cleansed by washing.

But this stone being very rare, the verditer commonly us'd is not a native, but a factitious substance; which some say is prepared by casting wine or water upon new copper, as it comes red-hot out of the furnace, and catching the steams that rise from it upon copper-plates: others again say, it is prepar'd by dissolving copper-plates in wine, much after the manner of verdegrease.

But the method of making it in England is as follows:

The refiners pour their copper-water into an hundred pound weight of whiting, stirring them well together every day for some hours, 'till the water grows pale; then they pour that off, and set it by for further use, and pour on more of the green water, repeating this 'till the verditer is made; which they then take out, and lay on large pieces of chalk in the fun to dry.

The water which is pour'd off from the verditer, (which remains at the bottom of the tub) is put into a copper, and boil'd 'cill it comes to the confidence of water-gruel; now consisting principally of salt-petre reduc'd, most of the spirit of vitriol being gone with the copper into the verditer: and a dish full of this being put into the other materials for aqua-fortis, is redistill'd, and makes what they call a double water, which is near twice as good as that made without it.

Dictionarium polygraphicum. Verdigris, verdegrease.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Verdigris, verdegrease is a kind of rust of copper, of considerable use in painting for green colour. It is a preparation made of plates of copper, and the husks of grapes well-saturated with wine, put up in earthen pots, and dispos'd layer upon layer, i. e. first husks and then copper; and this repeated 'till the vessel is moderately fill'd.

These pots are afterwards set in a cellar, where they are let to stand sometime, and then taken out, to gather the verdegrease, which is a green rust, with which the plates are covered all over.

The greatest part of the verdegrease us'd in Europe, comes from Languedoc in France, being made of the husks of the grapes of that country, and is brought over in cakes of about twenty-five pound weight.

The crystalliz'd verdegrease, or crystals of verdegrease, or calcin'd or distill'd verdegrease, is verdegrease dissolv'd in distill'd vinegar, and afterwards filtred, evaporated, and crystalliz'd in a cellar. This is us'd by painters to make a green colour, especially in miniature; it makes a beautiful transparent green for japanning on glass, being ground with oil of turpentine, and mix'd with common varnish, and leaf-gold or silver laid on the backside of it.

This commonly comes from Holland, or Lyons in France, and on sticks in form like our sugar-candy. To be good, these crystals must be beautiful, clean, and transparent, very dry, and as feee from sticks as possible.

Crystals of verdegrease are likewise made by dissolving copper, granulated in spirit of nitre, and afterwards evaporating to a scum or pellicle, and setting it in a cellar to crystallize.

Verdegrease is the plague of all colours, and enough to spoil a whole picture in oil-painting, if the least part of it enters into the priming of the cloth, yet 'tis a beautiful and agreeable colour; sometimes 'tis calcinated to take off its malignity; but 'tis dangerous to calcinate, as well as red arsenick; and let it be ever so well purified, it must be used alone, for it will spoil all the colours that are mix'd with it.

It is made use of, because it dries very much; and only a little of it is us'd, mix'd in blacks, which never dry alone.

The painter ought to take care, that he does not use the pencil with which he painted verdegrease in any other colours.

Dictionarium Polygraphicum. Containing. Polygraphick Dictionary. T. Tan. Tanner. Tanners Mill. Teints. To colour tin or copper of a gold colour.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Tan, the bark of a young oak beaten small, and us'd by cur riers for the tanning or dressing of leather.

Tanner, one who dresses hides, &c. by tanning, so as to make leather of them: he uses much bark in the way of his employment, concerning which there are several terms.
1. Scutching the bark, which is the cleansing it from moss, and the rough crusty outward rind, with an instrument call'd a scutching-knise.
2. Hewing the bark, that is, chopping it into small pieces.
3. Grinding it, by putting it under the mill to grind it small.
4. Drying the bark, which is drying it, that it may grind.
5. Setting down.
6. Stretching.
7. Laying down.

Tanners Mill, an engine made use of by tanners for the grinding and crushing their bark; being a large, round, wooden trough, with a pretty big stone set on edge, or turning part, with sharp strong knives, leaded into the stone; which stone being turned in the trough, causes the irons to cut the bark very small.

Teints and semi-teints [in Painting, &c.] are the several colours us'd in a picture, considered as more or less high, or bright or deep, or thin or weakened, or diminish'd, &c. to give the proper relievo or softness, or distance, &c. of the several objects.

To colour tin or copper of a gold colour. Set linseed-oil on the fire, scum it well, and put in amber and hepatic aloes, of each a like quantity; stir them well together 'till it grows thick; then take it off, cover it close, and set it in the earth for three days: when you use it, strike the metal all over with it with a pencil-brush, let it dry, and it will be of a golden colour.

Dictionarium polygraphicum. Varnish, vernish.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Varnish, vernish is a thick, viscid, shining liquor, used by painters, gilders, and various other artificers, to give a gloss and lustre to their works; as also to defend them from the weather, dust, &c.

There are several kinds of varnishes in use; as the siccative or drying varnish, made of oil of aspin, turpentine and sandarach melted together.

White varnish, call'd also Venetian varnish, made of oil of turpentine, fine turpentine and mastic.

Spirit of wine varnish, made of sandarach, white amber, gum elemi and mastick; serving to gild leathery picture-frames, &c. withal.

Gilt varnish, made of linseed oil, sandarach, aloes, gum gutta and litharge of gold.

China varnish, made of gum lacca, colophony, mastic, and spirit of wine.

Common varnish, which is only common turpentine, dissolv'd in oil of turpentine.


To choose spirits.
To make varnish, you must have spirit of wine, which must be strong, or else it will spoil the varnish, and not dissolve the gums; the stronger the spirits are, the better will the varnish prove. To try the spirits, put some into a spoon that has gunpowder in it, set fire to it as you do to brandy, and if it burns so long as to fire the gunpowder, 'tis fit for use.

To choose Seed-Lack.
The best is that which is large grain'd, bright and clear, freest from sticks and dross.

Gum sandarach.
The best is the largest grain'd and whitest, let it be as clear from dust as possible.

Gum Animæ.
The whitest, clearest, and most transparent, is the best.

Venice Turpentine
The clearest, finest and whitest is the best.

Of Rosin.
There are two sorts, the white sort should be very white and clear. Of the common sort, the best is clarified and transparent.

Gum Copal.
The best is the whitest, as free from dross as you can get it. It is a thick whitish heavy gum, seldom with out dross.

Gum Elemi.
The best is the hardest, whitest, and clearest from dross; it is brought over commonly in the bark of a tree.

Gum Benjamin.
The best is that of a bright reddish colour, like clarify'd rosin.

Isinglass.
The best is the clearest and whitest.

Gum Mastick.
The best is the whitest, largest grain'd, clear and free from dross.

The Dutch rushes and Tripoly, are to be had at the iron-mongers. The brushes and common size, always ready made at the colour



White varnish, amber varnish

From a manuscript of Mr. Boyle.

Take white rosin four drachms, melt it over the fire in a clean glaz'd pipkin, then put into it two ounces of the whitest amber you can get (finely powder'd.) This is to be put in by a little and a little, gradually, keeping it stir ring all the while with a small stick, over a gentle fire, till it dissolves, pouring in now and then a little oil of turpentine, as you find it growing stiff; and continue so to do till all your amber is melted.

But great care must be taken not to set the house on fire, for the very Vapours of the oil of turpentine will take fire by heat only; but if it shall happen so to do, immediately put a flat board or wet blanket over the fiery pot, and by keeping the air from it, you will put it our, or suffocate it.

Therefore it will be best to melt the rosin, in a glass of a cylindrick figure, in a bed of hot sand, after the glass has been well anneal'd or warm'd by degrees in the sand, under which you must keep a gentle fire.

When the varnish has been thus made, pour it into a coarse linnen bag, and press it between two hot boards of oak or flat plates of iron; after which it may be used with any colours in painting, and also for varnishing them over when painted.

But for covering gold, you must use the following varnish: this is to be observ'd, that when you have varnish'd with white varnish, you may put the things varnish'd into a declining oven, which will harden the varnish.


A hard Varnish, which will bear the muffle (from a manuscript of Mt. Boyle's) for laying over any metal, that appears like gold, to prevent it from turning black, which all but gold will be apt to do, when expos'd to the air.

Take of colophony, which is to be had at the Druggists, an ounce; set it over the fire in a well-glaz'd earthen vessel, till it is melted; then by little and little, strew in two ounces of powder of amber, keeping stirring it all the while with a sticks and when you perceive it begin to harden or resist the stick, then put in a little turpentine oil, which will thin and soften it immediately; then put in two ounces of gum copal (finely powder'd) sprinkling it in as you did the amber, ever and anon pouring in a little oil of turpentine; and when it is done, strain it as before directed.

This is proper to varnish over gold, and the things done with it, must be set into a declining oven, three or four days successively, and then it will resist even the fire.



Varnish for brass, to make it look like gold.

This is used upon leaf-gold, or upon that which is call'd Dutch or German leaf-gold, or upon brass or bath-metal, which are design'd to imitate gold.

Take two quarts of spirit of wine, and put it into a retort glass; then add to it an ounce of gambooge, two ounces of lake, and two ounces of gum mastic; set this in a sand-heat for six days, or else near a fire, or you may put the body of the retort frequently into warm water, and shake it two or three times a day; then set it over a pan of warm small-coal dust. Before you lay this varnish over the metal, to be sure you see that it has been well clean'd , varnish it over thinly with this varnish, and it will appear of the colour of gold. Set it in a declining oven tu harden, and it will not rub off. But for must use the following varnish:

N. B. This is a good varnish to mix with any colours that incline to red, and the white varnise for mixing with those that are pale.



A Varnish for wood, paper, &C.

The Japanese have a method of making plates, bowls, and other vessels of brown paper, and sometimes of fine saw-dust; which vessels are very light, and very strong, which by reason they are not liable to be broken by a fall as China ware or porcelaine made of earth, are much esteem'd with us. The method of making them is as follows.

Take brown paper, boil it in common water, stirring and mashing it all the while with a stick, till it is almost become a paste; then take it out and pound it well in a stone mortar, till it is redue'd to a soft pappy consistence, like rags for papermaking; then with common water and gum arabtc, a quantity sufficient to cover this paper-paste an inch, put these together in a well-glaz'd pipkin, and boil them well, keeping continually stirring them, till the paste is well impregnated with the gum: then is your paste fit for making any form you design.

Having the mould ready made, as suppose any thing of the figure of a plate, you must have hard wood turn'd on one side ot such a figure, with a hole or two in the middle, quite through the wood, to let any water pass through that is press'd out of the paste; which mould must be concave, and in the middle in the form of the underside of a plate, also another piece of hard wood must also be turn'd convex in the middle, and in the form of the upperside of a plate; this must be about the eighth part of an inch less than the under mould: but about the rim or the edge, you may, if you please, have some little ornament carv'd or engraven in the wood.

These moulds must be well oil'd on the turn'd sides, as soon as they are made, and must be continued oiling, till they have been thoroughly drench'd with oil; and oil them well again just before you use them, to prevent the gumm'd paste from sticking to the wood set the under mould upon a strong table even, and spread it over with some of your paste as evenly as you possibly can, so as to be every where of an even thickness of about a quarter of an inch; then having oil'd the upper mould, and put it as exactly as may be on the paste, press it hard down, setting a great weight upon it; letting it remain in that state for twenty-four hours.

When you suppose the paste to be dry, take it out of the moulds; and when it is thoroughly dry, it will be as hard as wood, and be sit to lay a ground upon, made with strong size and lamp-black, letting it dry gently; and when that is tho roughly dry, mix ivory-black with the following varsish, and use it as hereafter directed.



A strong Japan Varnish.

Take an ounce of colophony, and melt it in a well-glaz'd earthen vessel; then having three ounces of amber finely pulverii'd and sifted, put it in by little and little, adding now and then some spirit of turpentine. When it is thoroughly melted, sprinkle in three ounces of sarcocolla, keeping it all the while stirring, putting in frequently more spirit of turpentine, till all is melted, and well incorporated; then strain it through a coarse bair bag, plac'd between two hot boards, and press it genrJy, receiving the clear into a well-glaz'd pot, made warm. With this varnish mix the ground ivory-black, and having first warm'd the vessel made in the mould, whatsoever form it is, plate, bowl, &c. lay it on before the fire in a warm room, that the air may not chill the varnish: lay it on equally, and then set it into a gentle oven; and the next day into a hotter, and the third day into one that is very hot, letting it stand in it till the oven is quite cold, and then it will be fit for any use, either for liquors cold or hot, and will never change, nor can be broken but with great difficulty.

As for the moulds, it is probable they might do as well if they were cast of any hard metal, as if turn'd of wood.

You may also make what things you please of fineiaw-duft, by drying it well, and pouring on it some turpentine; having an equal quantity of rosin melted with it, and half the quantity of bees-wax, mix them well together, and put them to the dry lawdust, stirring all together till the mixture becomes thick as a paste; then take it off the fire, and having warm'd your moulds, spread some of the mixture on the under mould, that has a hole in the middle, as equally as possible, and press the upner mould upon it, as before; let it stand to cool, and your vessel will be fit for painting.

There may, if you please, be some sarcocolla finely powderd, put into this while your turpentine is melting, to the quantity of naif the turpentine; stirring it well, and it will harden ir: this varnish will most sasely be made in the open air, because it will endanger the house, and have a wet cloth ready to put it out, if it takes fire.

But which-ever of the mixtures you use, if you have a mind to have them appear like gold, do them over with gold size, and when that begins to stick a little on the finger, lay on leafgold, either real gold, or that which is brought from German:; but the last is apt to change green, as most of the preparations from brass will do. Such as those which aro call'd bath-metal, and others of the like sort, which appear like gold, when they are fresh polish'd, or clean'd every day; but as the air coming upon them will make them alter to another colour, gold itself is rather to be chosen, which is durable, and will never change, and is also a much finer colour than any of the former for a continuance.

And altho' the leaf-gold is tender, and may be supposed to be liable to rub off, yet the varnish, with which it is to be varnish'd over, will keep it bright and intire.

When the leaf-gold has been laid on, and the flying pieces brush'd off, which is not to be done till the gold size is dry; then varnish it over with the following varnish.



Varnish for gold, or such leaf of metals that imitate gold.

Take colophony, and having melted it, put in two ounces of amber finely powder'd, and some spirit of turpentine, and as the amber thickens, keep it well stirring; then put in an ounce of gum elemi, well pulveriz'd, and more spirit of turpentine, constantly stirring the liquor till all is well mix'd and incorporated: but take care however to use as little turpentine as you can; because the thicker the varnish is made, the harder it will be. Let this be done over a sand-hear, in an open glass, then strain it, as is directed for the preceding varnish. This varnish is to be used alone; first warming the vessels made of paper-paste, and lay it on with a painting brush before the fire, but not too near, lest the fire raise it into blisters. After this has been done, harden it three several times in ovens; first with a flack heat, the next with a warmer, and the third with a very hot one; and the vessels will look like polish'd gold.

And as for such vessels, &c. as shall be made with saw-dust and gums; the varnish may be made of the same ingredients as above-mention'd, except the gum elemi; and this will dry in the sun, or in a gentle warmth.



To varnish of a red colour.

After what you would varnish has been prepar'd as before, and is thoroughly dry, mix vermilion with the third varnish, and use it warm; then stove it, or harden it by degrees in an oven; and it will appear very glossy, or else lay on your first sround with size and vermilion, and in proper places you may ick on with gum arabick, and water some figures cut out of prints, as little sprigs of flowers, or such like; and when they are dry, paint them over with gold size, and let that remain till it is a little sticky to the touch; then lay on your gold, and let that be well clos'd to the gold size, and dried. See the article GILDING. Then if you would shade any part of your flower, take some ox-gall, and with a fine Camel's-hair pencil, trace over the shady parts on the leaf-gold, and with deep Dutch pink; and when that is dry, use your varnish in a warm place (I mean that varnish directed for the covering of gold) and se it to harden by degrees in an oven, which varnish will secure the leaf-gold; altho' it be only that call'd Dutch gold, or metal, from changing by keeping the air from it.



Varnishing any thing which is covered with leaf-silver.

First paint the things over with size, and ground chalk or whiting; let them stand 'till they are thoroughly dry, and then do them over with very good gold size, of a bright colour: (set there is much difference in the colour of it; some being yellow, and others almost white; the first is most proper forgold, and the last for silver.) When this size is almost dry, that it will just stick a little to the touch, lay on the leaf-silver, am close it well to the size. See the article GILDING.


A Varnish for covering silver.

Melt in a well-glaz'd pipkin some fine turpentine, and put m three ounces of white amber finely powdered, (more or lets according as the quantity your work will require) put it in by little and little, keeping it continually stirring, adding by degrees some spirit of turpentine 'till all the amber is dissolved; and then add to it an ounce of sarcocolla well-beaten, and an ounce of gum-elemi well levigated, adding now and then a little spirit of turpentine, 'till all is dissolved: do this over a gentle fire, and keep it constantly stirring.

This varnish will be white and strong as the former, and is to be used warm, and hardened by degrees in an oven, as varnished gold, and it will look like polished silver.



Varnish for wood to mix with several colours.

Take spirit of turpentine, and dissolve it in a little gum tttcamahacca over the fire, 'till, it is a little thickened; and this may be uled with any colour, that his been well ground with water, end afterwards reduced to a fine powder. When the work is done, you may, if you please, varnish over your piece with the same varnish directed for silver and wood, tables, tea-boaros, or any thing else may be done in the same manner, as is directed for vessels made of the paste of paper and saw-dust.



Varnishing Prints, &c. with white varnish, so as to bear water and polishing.

The print should be first pasted either on board or shock cloth, strained on a frame; in order to do this well, prepare some stiff starch; and with a spunge dipt in water, or thin starch (with out any blue in it) wet the back of your print: and if you design to lay it on a board, dip a large brush in thick starch, and brush it over the board as even as possible, and let it dry (or you may lay a ground of whiting and size on the board first, which will do very well) then repeat it a second time, and so continue 'till the veins or grain of the wood is quite filled.

In the last operation, when the starch is just laid on, lay the wet print upon it, as smooth as possible, that there may be no wrinkles nor bubbles in it, and press it on close every where, till it lies smooth, and so set it by to dry; which it will be, and it to varnish in twenty-four hours, with the following varnish:

Take Ichtyocolla, or fish-glue, or ising-glass, two ounces, and after you have pulled it into small pieces, boil it in a pint of brandy, or strong spirits, in a well-glaz'd earthen vessel, 'till it comes to a strong glue, which you may know by raking out a little, and exposing it to the air; it is then fit for your purpose, but don't fail to make it as strong as you can.

And while it is hot, with a large brush, brush over the print as quick as you can, and as smooth and even as may be; set it by for a day or two, and then do it over again with the same varnish or glue, and let it dry again very well; then brush it over with white varnish at such a distance from the fire, that it may not blister. Repeat this two or three times; then let it stand for a day or two, and then varnissi it over again with ihe white varnish the third time, with two or three passages of the brush; then let it stand for three or four days, and it will be hard enough to be polished, which is to be done with a soft linnen cloth and some Tripoli, rubbing it very gently, 'till it is at smooth as may be, and afterwards clear it with flour and oil, and then it will appear as clear as glass; and if at any time it is sullied with fly-shits, you may clean it, by washing it with a spungc and water.



The white Varnish.

Take gum sandarach, of the clearest and whitest sort, eight ounces; gummastick, of the clearest sort, half an ounce; of sarcocolla, the whitest, three quarters of an ounce; Venice turpentine, an ounce and a half; Benzoin, the clearest, one quarter of an ounce; white rosin, one quarrer of an ounce; gum animæ three quarters of an ounce: let all these be dissolved, and mix'd in the manner following;

Put the sarcocolla and rosin into a little more spirits than will cover them to dissolve; then add the Benzoin, gum animæ:, and Venice turpentine, into either a glass or glaz'd earthen vessel, and pour on as much spirits as will cover them an inch; then put your gum mastick into a glass or glaz'd vessel, and pour strong spirits upon it, covering it also about an inch thick, to dissolve it rightly; then put your gum elemi in a distinct vessel as before, and cover it with spirits to dissolve.

For this purpose, you need only break the rosin a little, and powder the gum animæ, sarcocolla, and benzoin.

Let all stand threeor four daysto dissolve, shaking the glasses, &c. two or three times a day, and afterwards put them all together into a glaz'd vessel, stirring them well, and strain the liquor and gums gently, beginning with the gums, through a linnen cloth.

Then put it into a bottle, and let it stand a week before yen use it, and pour osf as much of the clear only, as you think sufficient for present use.



To paste prints upon cloth for varnishing.

If the print be put upon a shock cloth, well strained in a frame, brush the cloth over with strong paste, made with flour and water; and immediately brush over the back of the print with well-prepar'd starch, and then brush the cloth over wri the same starch, and lay on the print as smooth as possible, with out leaving any wrinkles or bubbles in the paper. This you should rake notice of, that when you have laid your paper upon the cloth, they will both together appear flagging and unstrained, but as soon as they are dry, all will be smooth, as either of them was at first.

Let them stand so in a dry warm place for a day or two, and then you may varnish your print as before directed, with glue made of Ichthyocolla, and then with the white varnish.

With this varnish you may mix up any colour, that has been ground dry, with a marble, and paint it upon any figure you have drawn, or upon any print you have pasted upon your work; but the varnished colours should be chiefly put upon the shady.



Varnish made with seed lacca.

Take a quart of strong spirit of wine, put into a glass vessel, and put to it six ounces of seed-lacca, and let them stand together for two days, shaking them often; then pass it through a jelly-bag, or a flannel-bag, made like what is called Hippocrater's sleeve, letting the liquor drop into a well-glaz'd vessel, and giving the gums a squeeze every now and then. When the vrnish is almost out of the bag, add more, and press it gendy 'till all is strained, and the dregs remain dry.

Be sure you do not throw the dregs into the fire, for they will endanger setting the house on fire.

Put the varnish up in a bottle, and keep it close stopp'd, setting it by, 'till all the thick parts are settled to the bottom, which they will do in three or four days; then pour off the clear into a fresh bottle, and it will be fit for use.

As for varnish made of shell-lacca, it is not of any grew service, tho' so often recommended, for it will not bear the polish.

When you lay on your varnishes, take the following method;

1. If you varnish wood, let your wood be very smooth, close-grain'd, free from grease, and rubb'd with rushes.

2. Lay on your colours as smooth as possible, andiftheuarxijb has any blisters in it, take them osf by a polish with rushes.

3. While you are varnishing, keep your work warm, but not too hot.

4. In laying on your varnish, begin in the middle, and stroke the brush to the outside, then to another extreme part, and so on 'till all be covered; for if you begin at the edges, the brush will leave blots there, and make the work unequal.

5. In fine works use the finest Tripoli in polishing: do not polish it at one time only, but after the first time, let it dry for two or three days, and polish it again for the last time.

6. In the first polishing you must use a good deal of Tripoli, but in the next a very little will serve; when you have done, wash off your Tripoli with a spunge and water; dry the varnish with a dry linnen rag, and clear the work; if a white ground, with oil and whitine; or if black, with oil and lamp-black.



VARNISH [with Potters, &c.] is a sort of shining plaister, with which potters-ware, Delft-ware, China-ware, &c. are covered, which gives them a smoothness and lustre: melted lead is the varnish us'd for the first, and finals for the second.



VARNISH [with Medalists] is also a name given to the colours, which antique medals have got in the earth.

The beauty, which nature alone is able to give to medals, and art has never yet attain'd to counterfeit, enhances the value of them; that is the colour, which certain soils (in which they have a long time lain) tinges the metals withal; some of which are blue, almost as beautiful as the Turquois; others with an inimitable vermilion colour; others with a certain shining polish'd brown, vastly finer than Brasil figures.

The most usual varnish is a beautiful green, which hangs to the finest strokes without effacing them, more accurately thaa the finest enamel does on metals.

No metal but brass is susceptible of this; for the green rust, that gathers on silver, always spoils it; and it must be got off with vinegar or lemon-juice.

Falsifiers of medals have a false or modern varnish, which they use on their counterfeits, to give them the appearance, or air, of being antique. But this may be discovered by its softness, it being softer than the natural varnish, which is as hard as the metal itself.

Some deposite their spurious metals in the earth for a considerable time; by which means they contract a sort of varnish, which may impose upon the less knowing; others use sal-armoniac, and others burnt paper.



Varnish for Glass.

Take oil of turpentine six ounces, Venice turpentine three ounces, gum hederæ, i.e. gum of ivy (or rather mastich) one ounce, put them into a glass-bottle, stop it well, and wax it, that no vapours may come forth; then dissolve it in balneo mariæ, which will be done in about two hours time.


An useful Varnish.

Take drying linseed-oil, set it on the fire, and dissolve, it in some good rosin, or (which is better, but dearer) gum-lacca; let the quantity be such as may make the oil thick as a balsam. When the rosin or gum is dissolved, you may either work it ot itself, or add to it some colour, as verdigrease, for a green; or amber, tor an hair-colour; or indigo and white, for a light blue.

This will secure timber-work done over with it, equal to painting with colours in oil, and is much more easy to obtain; for linseed-oil and rosin are more easily melted together by boiling, than colours can any ways be ground; and being of the consistence of a balsam, works very readily with a brush, and of itself, without the addition of colours, bears a body sufficient to secure all manner of timber-work, equal to most oil-colours.

In the working of it, there's no great skill required, if you can but use a painter's brush; only let the matter you lay it on be thoroughly drenched, that the outside may be glared with it: and if you desire a colour on the outside, you need only grind a colour with the last varnish you lay on.


General Rules to be observed in Varnishing.

Let your wood be close-grain'd, exempt from all knots and greasiness, very smooth, and well rush'd. You must work in a room with a good fire, because your work must be always warm, but never put it so near the fire as to scorch it, or make it quite hot; for that will blister and crack it, which is a damage can never be repaired. When you lay the grounds, warmyoor work before every wash, and keep it in a gentle heat always, while 'tis drying. When 'tis ready for the pictures, rub the wrong side of the prints with starch, and six them on as flat as possible, that there may be no blisters, nor any part which is nor fix'd down close with the starch; otherwise the edges will be apt to rise, and will always lie rough. When they are dry'd on, pass them over with a small pencil dipt in common die (which you must have ready melted) to secure the colours from running; when that is dry, you may begin to varnish.

When you begin the varnishing stroke, fix your brush in the middle or the work, and with a quick steady hand, draw it to the other end. Then fix it again on the place you begun at, and draw it to the other end; thus you must do 'till it is all varnished. The reason for this caution is, that if you drew your pencil from end to end, the brush being over-charg'd at first, the varnish wou'd run over the edges of your work. Never pass your brush twice over the same place while 'tis [-], or that will make it lie rough.

Stroke your brush once or twice against the side of the pot, every time you dip it to take varnish, that it may not be too full: for the thinner you lay on the varnish (each time) the smoother it will be, and not so liable to speck and bubble. Continue varnishiug 'till the ground and pictures lie even; that is to say, that the ground be as high as the prinrs, and it all looks smooth and even. You must not omit varnishing it once every day 'till it is finished; then let it lie three weeks, or a month, before you polish it.


To polish.
There are three several ways to polish, which I shall give you all. First is, a pumice-stone steeped and melted in water; smear your work with it, and rub it with felt, 'nil all the strokes of the pencil disappear; then wash it off with cold water, and wipe it off with a soft cloth or muslin.

The second is, the dust which comes from sawing of stones, finely sifted, and us'd like the pumice-stone.

The third is with tripoli. Wrap a piece of very fine old linnen about your fore-finger. Dip it in water, then into the tripoli, which must be scrap'd with a piece of glass, or otherwise reduced to a very fine powder, without the least grittiness, for that would ruin all. Let your hand be moderately hard, and very even in all your polishing strokes. Polish and brighten one place, as much as for that time you intend to do, before you pass to another.

Remember not to polish your work, as smooth as you intend at one time: but let it rest two or three days, and then give it the finishing stroke. Take a large quantity of tripoli for the first polishing, 'till it begins to become smooth; the second time a small quantity will suffice. Let your endeavours be chiefly to polish the ground; for that being plain, will shew all faults the more.

To clear it up, wash off the tripoli with a spunge and water, and wipe it dry with a fine soft cloth: mix oil and lamp-black together, and with that anoint your work all over. Then take another soft cloth, and with a nimble quick stroke, and a hard hand, take the oil entirely os£ and you will find it answer tbe pains you have been at.

This way of clearing serves for all but the white and yellows, where instead of lamp-black, you must mix fine flower with the oil. And in the polishing, your hand must not be so heavy as in polishing other colours.



To make Gold size.

Take of gum-animæ half an ounce, gum-aspaltum half an ounce, litharge of gold a quarter of an ounce, red-lead and brown-umber, of each a quarter of an ounce; put all these into a new earthen pipkin, that holds one third more than you put in: put in half a quarter of a pint of linseed-oil, and a quarter of a pin: of drying oil. Set the pipkin over a gentle fire, that does no: flame out in the least; let it but just bubble up, or almost boil, tor should it run over, it would fire the chimney. As soon as it begins to bubble or boil, keep stirring it with a stick 'rill the gums are all melted thoroughly, and that it becomes thick and ropy like treacle, then 'tis boil'd enough. Take it off the fire, and when the extremity of the heat is over, then strain it through a coarse linnen cloth into another earthen pot, there to cool and lie ready for use. When you use it, put some of it into a muscle-shell, with as much oil of turpentine as will dissolve the size, and make it as thin as the muddy part of the seed-lac varnish: hold it over a candle, and when melted, strain it through a linnen rag into another shell; add to it as much vermilion as will make it of a darkish red.

Draw the figure or pattern, which you design to gild, after the ground of your work is laid; then with a pencil, propotioned to the work, lay the size neatly on those places you intend to gild, and no other. Let it stand 'till it is so dry, that when you touch it with your finger it may be glutinous and clammv, and stick a little; but not so moist, that the least spot or speck should come off with your fingers, not unlike to thick glue when 'tis half dry. When it just answers this description, take a piece of wash-leather, rap it round your fore-finger, and dip it inro your gold-dust (which you must have ready in a paper) and rub all over where the gold size is laid. If any should be sprinkled about your work, sweep it into the paper again with a clean pencil that has been us'd. When your gold is dry, secure it with the following varnish:



The securing Varnish to be used only in gold work.

Take of the best Venice turpentine, as much as you please, put it into a pipkin that will hold double the quantity you put in; set it over a clear gentle fire, and be cautious it does not boil over. When it boils, which must be very gently, keep it always stirring with a stick 'till it is boil'd enough, which you may know by pouring some on the ground; for when 'tis cold, it will crumble into powder between your fingers. When it is sufficiently boil'd, let it cool, and keep it for the following use.

Take a quarter of a pint of the clearest seed-lac varnish, and one ounce of the turpentine finely powder'd; put them into a double glass-vial, large enough to contain twice as much; stop it close, and set it over a very gentle fire, that it heat leisurely, to prevent the bottle's breaking. Whenit is very hot, the dan ger is past: fet it just bubble up for a little time; then take it off, and unstop the bottle, shaking it well: stop it again, and set it on the fire to bubble as before. Let it continue 'till the turpentine be dissolv'd to the bigness of a large pea, that being the dross, will not incorporate with the rest; take it off, and let it stand two days to settle, pour it off clear, and keep it for use. As this is only to secure the gold, you must be very careful in laying it on, that it touch not the least part of your ground, nor any thing but the gold. If there are colours mix'd amongst it, finish it up with the white varnish. If the design be all gold, finish it with the following varnish.

N.B. The Gold must be pass'd over twice or thrice with the securing Varnish.


The finishing Varnish for gold-work.

Take one pound of Venice turpentine, three pints of water; put them into an earthen pipkin, big enough to hold twice the quantity; place them over a gentle fire, and let it warm by de grees 'till it begins to bubble up: then keeping it always stirring with a stick, that it may boil leisurely for sometime, pour some of this liquor on the ground; and when it is cold, if it crumbles to powder in your fingers, it is boil'd enough. Set it by 'till it is cool enough to take into your hands, and squeeze the water entirely out of it; then make it into a ball, and after a day or two beat it into fine powder for your use; set it in a very dry place, but not near the fire, for that will melt it. Put one ounce of this powder'd turpentine to half a pint of the best seed-lac varnish; put it in a bottle that will hold twice as much close stopp'd; when it has stood sometime on a gentle fire, take it off, unstop, and shake it. Continue this 'till the turpentine be dissolved to the bigness of a large pea; set it by two days to cool and settle, then pour off the clearest for your work. Six or eight times varnishing will do, but you must use your own judgment according to the colour of the gold. Let it stand three weeks or a month before you polish.

Dictionarium polygraphicum. Turmerick.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
Turmerick is a root us'd by dyers to give a yellow colour. This root is yellow both within and without side, very hard, as if petrified, and not unlike either in figure or size to ginger. The leaves it produces are like those of black hellebore; its flowers rise in manner of a spica, or ear, and its fruit is rough like new chesnuts.

It comes chiefly from the East-Indies; though it grows allo in the island of Madagascar.

It should be chosen large, resinous, hard to break, and heavy.

Some persons have mistakenly imagined there was a native red turmerick; their error was owing to this, that the yellow root, as it grows old, turns brown, and when pulveriz'd, reddish.

It is much us'd by glovers, &c. to dye their gloves; as also by founders, &c. to give a gold colour to their metals.

The Indians use it to colour their rice and other foods yellow; for which reason, it is by some call'd English saffron.

Our dyers don't find it gives so steady a yellow as the luteola or greening weed; but it is admirable for brightening and heightening the red colours dyed with cochineal, or vermilion, as scarlets, &c.

Dictionarium polygraphicum. The way to make Turcoise.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
The way to make Turcoise.

The name of Turcoise, which this precious stone bears, comes from the place where it is found, viz. in Turkey; altho' this stone comes also from Persia and the East-Indies, where it is found in abundance, the colour whereof approaches nearer to blue than green, which also distinguishes them from those that come out of the west, which are more green and whitish.

They call the first by the name of the stone of the old rock, and the other by that of the new.

The Turcoise is the finest and noblest of all the opake precious stones: its colour is composed of green, white, and blue, and imitates that of verdigrease.

Take ten ounces of natural crystal prepared, and Saturnus glorificatus; half an ounce of purified verdigrease, and one ounce of our prepared zaffir, the whole in hue powder; which mix well together in a crucible covered, with another well-luted and dried, which afterwards put into a glass-house furnace, where leave it for three hours; then twelve hours in the annealing furnace, that it may cool gently; then take out your crucible, and break it, and take out the matter, and cut and polish it, and you'll have Turcoise-coloured stones like those of the old rock.



The way of making Turcoise-blue, a particular colour in this art.

For this colour take a pot-full of crystal-frit ringed with an aqua-marine colour, or blue, whereof we have given several preparations, which colour must be fair and full, for all depends on that: it being well-melted, put into it, little by little, sea-salt decrepitated white, and reduced to powder, mixing it well and softly, as we have noted in speaking of other metalline colours; and the blue, from clear and transparent, will become thick: for the salt penetrating the glass, takes away its transparency, and causes a paleness; hence alone comes the Turcoise-colour used in glass. When the colour is right, to the workman's fancy, it must be presently wrought, for the salt will evaporate, and make the glass transparent and disagreeable; if in working this metal the colour fades or goes off, you must add a little more of the same decrepitated salt, as before, and the colour will return.

We will here advertise the workman, that he mud take care, that this salt be well decrepitated, otherwise it will always crackle and be apt to fly in his eyes, and endanger his sight; you must (as I have said) put in the salt in intervals, 'till the colour pleases you.

It will suffice for this use, that the frit tinged aqua-marine, or blue, be made of one half crystal-metal, and the other of rochetta, and the colour will be very fair and good.

Dictionarium polygraphicum. Tragacanth, adracant.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
A kind of gum, oozing out at incisions, made in the trunk and larger branches of a plant, or little shrub of the same name.

Mr. Tournefort tells us, the naked hillocks of mount Ida in Candia produce a deal of the plant Tragacantha, which gives the gum spontaneously towards the end of June, and in the following months; when the nutritious juice of the plant, thickened by the heat, bursts most of the vessels it is contain'd in.

This juice coagulates in threads, which make their way into the pores of the bark; where being push'd forwards by new juice, they get through the bark, and are at length hardened in the air, cither into little lumps, or into twisted pieces, in form of little worms, longer or shorter, according to the matter of which they are form'd.

This plant grows also in several places of the Levant, par ticularly about Aleppo.

The gum is of different colours and qualities; some being white, others greyish; some red, and some almost black: but the white is the best.

It should be chosen clear, smooth, and twisted, like little worms.

Dictionarium polygraphicum. To dye stuff a brown or tawny.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735
To dye stuff a brown or tawny.
Put a handful of madder into a kettle of hot water, stir it very well about, and let it stand and settle a while; moisten the stuff with it, then roll it up, and put it into the kettle upon the roll; and when you find that the colour docs no longer fall upon it, then add to it two handfuls of madder, and let it cool; and when you perceive it to be boiled to a half-red colour, throw in a pail-full of the black dye into the madder suds, stir them together, and make a wood-fire under the kettle: for having its proper heat, it turns the better to brown; and if it be not dark enough, throw in another pail of the black lye, or more, 'till it becomes of the colour you would have it; then work the stuff in it very well upon, or with, the roller, to hinder it from spotting.

Another tawney.
First give the stuffs a blue ground, which must be either light or deep, according as you would have the tawney.
Then alum them, boiling them an hour in the alum water; let them stand 'till they are cold, then rinse them out, and pass them through the madder red dye, and they will turn to a light tawney, as light or as deep as you would have them, according as they are blued; then rinse and cleanse them out.

A deep tawney.
Let the stuffs be first dyed a madder red, then take the dye off the fire, and put a quart of black dye into it for every pound of stuff; heat it, and put the stuffs into it, and work it fo long 'till it hath taken the dye sufficiently; then cool it, and it will be a lasting dye.

Another.
Dye the stuffs red, then boil them in the remainder of the black dye, boiled up (after it hath been used) 'till they are dark enough, then cool them and rinse them.
But if you would have the taviney light, take half of the black dye, and half water, and it will of consequence be so much thinner and weaker.

To dye a crimson tawney with cochineal.
Alum and prepare the silk as for crimson, then fill a clean kettle with fair water, and some blue wood suds, of each a like quantity, and then for every pound of silk put in one ounce of galls, one ounce and half of cochineal; and afterwards, having first rinsed the silks, put them in, stir them about carefully to pre vent their being variegated or spotted; because the Provence wood suds is apt to spot, if it be not violently stirr'd; let the silk lie one whole night in the suds, then rinse it out and dry it.

Another tawney.
First, lay the silk in a strong alum water for twenty-four hours, and for every pound of silk take one pound of good Brasil wood; boil it in a bag for full two hours, then take it out, and let the liquor stand, 'till you can just bear your hand in it, and afterwards put in the silk, and let it continue there an hour, then take it out and dry it; then boil the dye again, put it in again as before, then rinse it very clean; then beat some bole armoniac small, and mix it with beech ashes, to be made into a lye, which strain three or four times through a cloth; make it milkwarm, and then put in the silk; when it is deep enough dyed, rinse it, beat it, and dry it.

A lasting deep tawney.
Let the kettle be very clean, fill it with water, and to every pound of silk, put in one pound of blue wood, one pound of galls; boil them for an hour, then fill it up with gall-water, and while it is hot, put in and stir the silk, let it lie in 'till the next day, then rinse and dry it.

To dye silk a crimson deep tawney.
First prepare the silks (as directed for crimson) put a sufficient quantity of liquor into a clean kettle, and for every pound of silk, put in one pound of madder, one pound of galls, and half a pound of blue wood, and boil them together with the silk for an hour, putting the wood into a bag to prevent its hanging in the silk. Let the silk lie a whole night in the liquor, in the morning take it out, wring it, rinse it, and beat it well, then rinse it again; and afterwards beat and dry it.

A slighter sort of tawney.
This is prepar'd after the same manner with the red, with this difference; for every pound of silk take one pound of Brasil wood, and two ounces of Provence wood, manage the silk as in the red, and dye it.