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.
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.

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.

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