Valuable Secrets concerning Arts and Trades:
or Approved Directions, from the best Artists, for the Various Methods...
Printed by Thomas Hubbard,
Norwich, 1795
I. The method of gilding with fixe, or with oil.
The old leaves which are commonly used in gilding are of different sizes, as well as of various degrees of thickness, as there are some the thousand of which comes to no more than three pounds altogether, and others which come to three pounds ten shallings, and four pounds, per thousand.
To gild on iron and other metals, the strongest and the purest are preferable. That which is not so purest commonly employed by carvers in wood, as it come cheaper to them.
We are indebted to the discovery which has been made a few ages since, of the secret of painting in oil, for the means of gilding in such a manner as to refill the injuries of the weather. - An art the ancients were not acquainted with, and they could not obtain from their method of applying gold, since they used nothing else but whites of eggs for gilding marble, and such other bodies as do not admit of being committed to the fire. As for the wood, they made a composition which was used with size. But neither size nor whites of eggs can refill the water. Therefore they could not, with propriety, gild any other works than such as were sheltered from the intemperance of the weather, viz. their arches, their cielings, which were all gilt in that manner. The composition they used for gilding on wood was made of a slimy earth, which held the place of the fized white we use now-a-days, and with which gilders make that first coat, called by artists assiette, or burnish-gold size.
II. To gild with size, or, what is called in burnish-gold.
1. You must first begin by preparing your size, which is made as follows. - Take about a pound of odd bitts of parchment, or leather, such as is prepared for gloves or breeches. Put this a-boiling in a pailful of water, till it is reduced to one half, and your size is done as it ought to be.
2. When you want to use it for wood which is to be gilt, it must be boiling hot, otherwise it would not penetrate sufficiently into the wood. If you find it too strong, you may weaken it, by adding water to it. Then with a brush made of boar's bristles, you lay the size in smoothening, if it be a plain work; but, if a carved one, you must lay it in slumping with the brush; either of which ways is equally termed to size.
3. When the wood is thus prepared with size only, you must make another preparation, called an infusion of white, in the following manner. Take a certain quantity of size boiling hot, as much as you think will be sufficient for your work. Dilute a discretionable quantity of pulverised whitening in it, and let it infuse some time. When it seems well dissolved, strain it through a cloth to make it finer; then, with a brush, as above, give seven, or eight different coats of it in stumping on your work, and two more coats in smoothening, if it be on carved work; but if on a plain one, you must give a dozen of coats at least; for the white is the nourishment of gold, and serves to preserve it a great while. - You must be very careful not to give coat upon coat, unless the last be dry; otherwise the work might scale. You must even have a great care that each coat mould be laid on as perfectly equal as possible, both in the strength of the size, and thickness of the white, to avoid the same inconveniency.
4. When you have given the requisite number of coats, whether in stumping, or in smoothening, you must let the work dry thoroughly before you polish it. As soon therefore as it is perfectly dry, you must have a coarse rough cloth, quke new, and as closely weaved as possible, with little deal sticks, cut square, angular, or pecked, according as the nature and carving of the work require; and, thrusting one of these sticks into the cloth, you rub and smoothen the white. Then, taking a brush made of boar's bristles, which has been already used, because it is softer, dip it into some clean water, and wet the work in proportion as you go on in polishing, with your little sticks wrapped up in cloth. This precaution completes the smoothening of the work, by levelling the small bumps and imperceptible undulations you may have made either in giving the white, or in polishing it. For, the smoother the work is made, the more easy to be burnished the gold will be, after having been applied. The wetting and brushing thus your work, in proportion as you polish it, with a brush a little worn, has again that other objedl of cleaning it of the must you occasion in fb doing; therefore spare not to purge your brush of all the filth it gathers about the point of its hair, by washing and squeezing it again as ibonas you see them grow thick in the least with that dirt.
5. When the white is once more dried, rub it with shavegrass, or rushes, in order to level still better all the grains and inequalities which may be on it. Do not however rub it too much with the shavegrass, because you may thereby fall from one error into another, and make your white what is called greasy or smeary, which would prevent it afterwards from uniting with the burnish gold size, which is to precede the laying on the gold.
6. Now, as it is difficult that after ten or a dozen, of coats of white the carving should not be choaked up, they who are fond of finishing their work highly, take a certain iron instrument, made on purpose, and curved by one end, (called by the French, (fer-a-retirer); with this raffling-crook they go over all the turns, and open all the places which want it, to restore them to their former sharpness. Or else, you take what is called a fermoir, or a gouge, or a cizel, and give to the ornaments the same form which the carver observed when he first cut them, turning agreeably the sides of leaves according to nature; then bretelling with another instrument, called the veining-crook, (in French fermoir-a-nezrond), all the ornaments, you thereby render the work much neater, and more delicate than the carver had first made it. That you may cut the white more neat, observe only to wet it a little with a brush.
7. When works are not of great consequence, you may easily save yourself all that trouble; principally if the carving is pretty neatly finished, by giving two or three coats only of white very clear. But, as it is very true the white is the principal and only support of gold, this operation is never so perfect, nor stands so long; and the carving seems a great deal more rough than when it has received ten or twelve coats of white, and been afterwards re-cut, carved, veined, and repaired over again, as I said before.
8. After every thing has been performed about the white, which could be required to completely finish that preparatory part, you must dilute some yellow oeher, and grind it with sized water, weaker by half than that which you used for the whitening. And, having made it a little fluid and warm, you lay one coat of it over all the work, principally in such deep places of the carving as you cannot come at to lay the gold leaf, that this colour may supply its want.
9. When the yellow is dry, you must lay over it (in all the raised places, but not in the bottom grounds) three different coats of another sort of composition, called in French assiette, and here, burnish-gold size, made and prepared in the following manner. - Bol armenian, about the bigness of a nut, and grinded by itself; blood stone, or red chalk, the bulk of a horse bean, and blackhead pulverised as big as a pen, grinded both together; and at last one drop or two of tallow, which you grind afterwards with all the other drugs and water, taking them little at a time, to grind and incorporate them the better. - Put this composition in a cup, and pour over it some of your afore-mentioned size, boiling hot, and drained through a cloth. Stir and mix all well, while you pour that size, that the whole may be well diluted. The size you make use of in this case must, to be right, be of the considence of the jelly you eat, and no more, when cold. - There are those who mix again besides, with this composition, a little soap, or olive oil, with a little of calcined lamp, black. Others add burnt bread, bistre, antimony, tinglass, butter, sugarcandy, &c. every one according to his own way. All these sorts of grease serve to facilitate the burnishing of the gold, and help to give it more brightness. Be, however, this compolition made how it will, observe to keep it warm over hot ashes in t chaffing-dish, whenever and while you use it. The brush you lay it on with ought to be soft, and the first coat you lay pretty thin: but, as for the two others, they must be so thick that the stuff should run with difficulty from the brush. Each coat must be well dried before giving the next. And, when the last is also perfectly dry, take a stiffer brush with which you dry rub the work all over, to smoothen all the grains and little risings of the gold size, and thereby facilitate the burnishing of the gold.
10. The gilding is now performed as follows. Have first a pipkin very clean, in which you put some very clean and filtered water, and a few wetting pencils, which ought to be made in the form of those ermin tails which hang in the ermine skins. - Get next a cushion, which is to be made wish a light and flat square board covered with a calf leather, fixed all round with nails, and stuffed underneath with cotton. Let the cushion be also surrounded by the back part, and two thirds of each of the two rules, with a band of parchment of five or six inches high, to prevent the air, which is always fluctuating about you, and still more so if any body should happen to pass and repass in the place where you fit, from blowing the gold leaf which is laid upon it.
11. To apply the gold, you proceed thus. Hold your cushion in your left hand along with the gilding pencils, which are to be of different sizes. On this cushion put what quantify of gold leaves you think proper. With the gilding knife spread these leaves very smooth, in doing of which you will assist yourself very much if you breath over them while you pass the knife under. Then cut it in as many parts and sizes as you want, or, if there be occasion for it whole, take it with your tip, and lay it. - A tip, (in French, palette), is an instrument made with the point of a squirel's tail placed upon a round stick flattened, and about half an inch wide by one end, with a slit, to set and spread the better the squirel's tail. - This tip therefore you pass along your cheek, and with it take off the gold leaf, or what part of it you have divided, and thus lay it on the work. Previously, however, to this, you must have passed on the place one of your pencils immediately before the laying of the gold, otherwise the gold would be incessantly flitting and cracking. - As soon as the gold leaf is laid on the work, take your water pencil quite wet, and passing it above it on the work, let the water run from it under the leaf just applied; this will immediately make it spread and ketch. But if it should pass over the gold leaf, it would immediately spot and spoil it; and as it is impossible to lay gold on gold, especially when wet, you would not be able to repair it unless you take the gold leaf entirely off, and put another in the stead. On the contrary, by the water slipping under the gold leaf just laid, you will find that this spreads infinitely more easy, and almost of itself; it sticks faster on the gold size, never scratches, is more easily dusted for burnishing, or matting with size; in short the work looks infinitely better in every respect. - As it is impossible with all possible care one can take, but there may happen some little accident now and then, principally in carved works, you must, in such a case, cut some small bits of gold, which, with a pencil, you take and put on the defective places when you look your work over; and this is called faulting the work, in French ramender.
12. When the work is perfectly dry, burnish it where you think proper, in order to detach certain parts from the other, to make them set off and shew to better advantage. To that effect you use an instrument called a burnisher, made either of a real Wolf's tooth, or rather, as they now use it, an agate, made in the same form, and finely polished, or else a pebble called blood stone. - Before burnishing, you must, with the crooked point of your burnisher, push down all the parts of gold in the hollow parts which you forgot to do with the pencil then dust it with a large one. When, the work is burnished where you want it to be so, you matt and repass, with a very soft pencil and burnish gold size, what has not been burnished; or, you may again put some vermilion, to raise the gold, and make it look brighter; which is called, in term of art, repassing.
13. There is again another repaying you must not forget, which is to lay, in all the hollow places of a carved work, a coat of a composition of vermilion, as I am going to prescribe, and which will give an incomparabic fire to the gold, and make it look as gold-smith's work. This composition is such. - Grind together, on marble, some vermilion, gamboge, and red brown, which you mix with a little Venetian turpentine, and oil of turpentine. There are who make it otherwise, and life only fine lake, and others, dragon's blood; but the first receipt is the best. - If, after having burnished, matted, and repassed your work, you find again some defective places, you may mend them with gold in shell, which, as you know, is diluted with a little gum arabic, and applied with a pencil. This sort of faulting, which is no small addition to the beauty and richness of the work, the French call buckling with gold in shell.
II. To gild without gold.
Put in a crucible one ounce of ammoniac salt, and half that quantity of common mercury. Cover and lute well the crucible for fear the mercury should exhale. Give this a small fire for the space of half an hour. Increase the fire afterwards till the crucible is quite red hot. Then throw the composition into a pan of cold water. As soon as this matter is cold, it will be as hard as a stone. Break and grind it, and dissolve it in gum water. Wherever you lay a coat of this, it will look like gilt.
III. Another for the same purpose.
To gild frames, and other common things, pulverise snd incorporate well together the yolk of an egg with two ounces of mercury, and one of ammoniac salt. Put this into a matrass, stop it well, and set it, for four and twenty days, in hot horse dung.
IV. A gild without gold.
Grind some purpurine with water; then put it to soak with chamber-lye in a pan; stir and skim it. When it has done throwing any scum, decant the chamber-lye, and supply it by gum water. Whatever you write or draw with this composition will look as gold itself; and it admits even of being burnished with the burnisher.
V. The preparations of the gum-water.
In half a pint of common water put two ounces of gum arabic, bruised in small bits. When dissolved, it makes the right degree of gum-water to be used for the above purpose.
VI. To write in gold or silver.
Draw the juice of juniper leaves. In this juice throw some gold or silver filings, which you set there to infuse for three whole days: then make the trial.
VII. To gild on glasses earthen, or china wares.
Take a glass, or a china cup; wet it, and lay your gold where and how you like, then let it dry. Dissolve some borax in water, and of this liquor lay a coat on your gold. Set it in the fire till your glass powder in melting makes a varnish on the gilded parts, which will then appear very beautiful.
VIII. To write or paint, in gold colour.
Pulverise some purpurine into subtile powder; then water it over, gently, and by little at a time, with chamber-lye, turning incessantly, while you pour, with a stick. Let it settle, and wash it in common water, so many times till you see the water comes out at last quite clear. Each time you change the water take particular care to allow a sufficient time for the settling. Then mix after the last water is poured awav, some powder of saffron gum-water with your ground, and either write or paint, which you like. This secret is by no means an indifferent one; and you will find it very agreeable if you try.
IX. To write, or paint, in silver, especially with a pencil.
Pound well, in a bell-metal mortar, some tin-glass; then grind, and dilate it, on porphyry, with common, water. Let it settle, and throw off the water, which will be black and dirty. Reiterate this lotion so many times till the water remains clear. Then dilute it in gum-water, and either write or paint with it. It will appear very hand some, and no ways inferior to the finest virgin silver.
X. To whiten and silver copper medals.
1. Take filings from Cornwall pester and make a bed of them at the bottom of a pipkin. On this bed lay one of your medals, taking care however they should not touch each other. Make another bed of filings over these medals, and one of medals again on these filings. Continue this alternate stratification of medals and filings, till you have laid all the medals you wanted to whiten.
2. When this is done, fill up your pan with water, and put on it a powder composed of roch-alum, and tartar from Montpellier, well grinded and mixed together. Boil the whole till the whitening of the medals is complete.
N. B. They must have previously been cleansed with soft sand, or strong lye, to purge them from any grease.
XI. A water to gild iron.
In three pounds of river-water, boil roch-alum, one ounce, Roman vitriol as much, verdigrise half an ounce, gem salt three, and orpine one. Then add tartar half an ounce, and the same quantity of common salt. Boil it attain with this addition. Now heat your iron, and when warm, rub it over with this stuff quite hot, then dry it by the fire, and burnish.
XII. To whiten exteriorly copper statues.
Take silver-crystals, ammoniac, gem, common and alkali, salts; of each of all these two drachms. Make all into a paste with common water. Lay your figures over with it, and set them on red hot charcoals till they smoak no more.
XIII. To write in gold letters on pots, or boxes.
Dissolve isinglass in water. When reduced into a size, or glue, dilute some red tartar with it, after having made it into a very subtile powder. With this mixture, and a pen, or a pencil, write on your pots or boxes; then put a thick gold leaf on it of the same sort as metal gilders use. And, when this is dry, burnish as usual.
XIV. To gild silver in water-gilding without the assistance, of mercury.
1. Take first the finest gold, forge it weakish, then cut it in bits and neal it, on an iron plate, or in a crucible.
2. Have next a glass matrass, put your gold in, and to every drachm of gold, put half a pound of ammoniac salt, and two ounces of good aquafortis. Cover the matrass with a sheet of paper, turned conically by one of its corners upon one of the long sides, so as to form a sort of funnel or grenadier's cap figure, with the smallest and not quite close, but terminated in a small orifice, to give, a free passage to the fumes of the aquafortis. Set this matrass on a very slow fire, that the gold may have time to dissolve gently and gradually, and shake often the matrass to help the dissolution. Be very careful not to make the fire too strong; but, on the contrary, let it be very mild, for the gold would infallibly sublime. and waste itself all into vapours.
3. When the gold is entirely dissolved, pour this liquor into a glass, or china bowl; wet some old coarse linen rags on them, which you set to drain on small sticks on another bowl, doing the same with what drains from them till you have used all your liquor; then dry them before a gentle fire,
4. When dry, lay them on a marble stone, and set them on fire. And as soon as they are consumed, grind them into a fine powder, which you put afterwards in, to a crucible on a little fire. When this powder is lighted like sparkles of fire, put it on the marble again, and stir it with an iron rod till you see no more fire. Grind it then again as before, as much as you possibly can, and it is fit for gilding any sort of silver work you please.
XV. The liquor, called the sauce, which is to be used for colouring silver plates, gilt with the above described powder.
1. Grind well together, into a subtile powder, sulphur and pearl ashes, of each one ounce, and two of common salt.
2. Then, when you want to colour your gilt plates, have a quart of water, and half a pint of chamber-lye, in which you mix a large spoonful of the above powder. Set this to boil in a red copper pot, very clean. When this sauce does boil, you must the your plate with a silver wire, by which you hold it, and then plunge it in; there leave it for about a minute, or two at most; then take it out again by the same wire without touching it with your hands, and plunge it in the same manner in cold clean water. Should it then not look high coloured to your satisfaction, you have but to put it again in the sauce, as before, till you find it sufficiently coloured.
3. The next step is to give the piece thus coloured to the burnisher, with a strict charge not to use any vinegar in his burnish. This receipt is a very good and particular secret.
XVI. A water which gilds copper and bronze.
A secret very useful for watch and pin makers. Dissolve equal parts of green vitriol and ammoniac salt in good double distilled vinegar; then vaporate the vinegar, and put it in the retort to distil. If in the product of the distillation you steep your metal after being polished and made hot, it will come out perfectly well gilt.
XVII. Another.
Take burnt copper and ammoniac salt, equal parts; alumen plumeum, four ounces; common salt decrepitated, as much. Dissolve the whole in double distilled vinegar, then vaporate this vinegar. Distil from the rest an aquafortis which, if you extinguish, five or six times, brass, copper, iron, or silver, made hot, these metals will assume the colour of gold.
XVIII. A water to gild steel or iron, after being well polished.
Take seven ounces of orpine; terra-merita, one and a half; socotrine aloes, four and a half; gamboge three and a half. Put all into powder, and put it in a retort, with so much of pickle water as will cover these powders by two fingers. Stir well, and mix all together; let it infuse four and twenty hours and distil. With the liquor which shall come from the distillation, and which you may keep by for use, rub the steel, iron, or copper, and iet it to dry in the shade.
XIX. To silver copper figures.
1. Cleanse well first the figures with a strong lye, made with either pearl or brill ashes, or common salt or alum, no matter which. Wipe them well when done, and rub them with a composition of tartar and ammoniac salt mixed (by means of aquafortis) with a little dissolution of silver.
2. Now with a piece of leather, wetted in your spittle, take of these powders, and rub the copper figures till they are sufficiently silvered.
XX. To silver, or gild, pewter.
1. Take one of the finest and most delicate goldsmith's wire-brush; rab your pewter with it so as to mark it with the strokes of the brush. When done, lay a double gold or silver leaf on that place of the pewter; then put over it a-piece offkin or leather, and over that skin some putty. With a burnisher rub, for a good while, on that putty; then with a piece of pewter oa the naked gold without either skin or putty.
2. Have a care that the pewter which you are thus a gilding should be very clean, and that your breath should net go over it. Therefore, to do that operation, you must put your handkerchief before your mouth, and manage it so in tying it, that there should be a passage preserved on each side of your face which should drive your breath along your cheeks, round your head, and quite up behind your ears.
XXI. A composition to lay on lead, tin, or any other metal, in order to hold fast the ready gilt leaves of pewter, which are applied on it; useful for gilding on high steeples, domes, &c.
1. Melt together, on a slow fire, black pitch pounds; oil of turpentine, four ounces; and a resin. When the whole is dissolved and mixed well to a kind of varnish, lay a coat of it on your work.
2. Now, as upon steeples, the common method of gilding cannot, on account of the wind, be practised; have only the exact measures and dimensions of the place intended to be gilt, then, at home, and at leisure, cut to them some fine leaves of pewter, and gild them as usual. When done, you have no more to do but to carry up these pewter leaves, rolled, in a basket; and, having burnished the place on which they are to be applied with the above composition, lay the gilt pewter leaves on it, and they will stand fail enough.
XXII. To clean and whiten silver.
1. Rasp four ounces of dry white soap in a dish. Pour a pint of warm water on it. - In another dish put a penny-worth of wine lye dried in cakes, and the same quantity of the same water. - In a third dish put also another penny-worth of pearl ashes, with another similar quantity of the same water.
2. Then, with a hair brush deeped first in the wine lye, then in the pearl ash, and lastly in the soap liquors, rub your silver plate, and wash it afterwards with warm water, and wipe it with a dry cloth kept on a horse before the fire for that purpose.
XXIII. The preparation of gold in shell.
Take ammoniac salt, and gold leaves, equal quantities. Bruise this in a mortar for two or three hours; and towards the end add a discretionable quantity of honey.
XXIV. To bronze in gold colour.
Rub the figure first with aquafortis, in order to cleanse and ungrease it well. Then grind, on porphyry, into a subtile powder, and mix with lintseed oil, equal qualities of terra merit a and gold litharage. With this composition paint the figure over.
XXV. Another to the same purpose.
Take gum elemy, twelve drachms, and melt it. Add one ounce of crude mercury, and two of ammoniac salt. Put all in a glass phial, and set it in a pot full of ashes; lute well the phial, and melt the contents. When perfectly dissolved, add a diferetionable quantity of orpine and brass filings; mix all well, and with a pencil paint what you will over with it.
XXVI. How to matt burnished gold.
Grind together, blood-stone and vermilion with the white-of an egg. Thea, with a pencil, lay it in the bottom grounds.
XXVII. How to do the same to burnish silver.
Grind ceruse-white with plain water first, then with a very weak isinglass water, and make the same use of this as of the other.
XXVIII. The method of applying gold, or silver, in shell, on the wood.
Black wood, or that which is dyed so, is the fittest to admit of this operation. The method of applying it is this.
1. Take a little gum adragant, which you dilute in a good deal of water, to make it weak. With this weak gum water dilute your gold or silver; and, with a pencil, lay it on such places of your work as receive and shew the light, without touching on those which are the shades. To express these, touch the parts with indigo diluted in a very weak gum-arabic water.
2. When this is done, lay one coat of drying varnish, made of oil of spike and sandarack. If the varnish be too thick, thin it with a little oil; and, in mixing it, take care not to boil it so hard but you may bear some on your hand without scalding the place.
N. B. Have attention to make your gum-waters for this sort of work always very weak; otherwise they would tarnish and spoil all the gold or silver.
XXIX. To gild sandy gold.
Take any colour, and grind it either with oil, or with gum. Lay a few coats of it on your work, according as you think there may be need of it. When dry, lay one coat of size, and while it is still fresh, sift some brass filings on it; let it dry so, and varnish it afterwards.
XXX. The varnish fit to be laid on gilding and silvering.
Grind verdigrise, on marble, with common water, in which you shall have infused saffron for eight hours.
XXXI. The method of bronzing.
Take three penny-worth of spal, one of litharage, a gill of lintseed oil, and boil the whole to the consistance of an unguent. Before you apply it, dilute the quantity you intend to make use of with turpentine oil, and lay a coat of vermilion on the work before bronzing.
XXXII. A water to gild iron with.
1. Put in a glass bottle, with a pint of river-water, one ounce of white copperas, and as much of white-alum; two drachms of verdigrise, and the same quantity of common salt. Boil all together to the reduction of one half. Then stop the bottle well for fear the contents should lose their strength.
2. To gild the iron with it, make it red hot in the fire, and plunge it in this liquor.
XXXIII. To make the fine writing gold.
1. Take gold in shell, and sulphur, in the proportion often drachms of this, well grinded on porphyry and amalgamated, to every sequin-worth of the other. Put this mixture into a proportionable leather bag, in which you mall work it continually for the space of two days. Then pour all into a crucible, and burn it on a slow fire. This done, warn what remains with filtered lime water, and, by filteration also, get your water out again from the composition. If, after this operation, you do not find it high enough yet in hue, warn it again and again in the same manner, till it looks fine.
2. To apply it, dilute some bol armenian with isinglass, and write what you please, and let it dry; then apply your gold, and when dry burnish it.
XXXIV. How to get the gold, or silver, out of gilt plates.
1. Mix together one ounce of aquafortis, and one of spring water, with half an ounce ot common, and one drachm of ammoniac, salts. Put all or the fire, and boil it; then put in to soak the plate from which you want to get the gold or filler out. A little while after, take your plate out, and scrape it over the liquor.
2. The gold will remain suspended in this regal-water; and to make a separation of them, pour in it double the quantity of common water; or again, throw a halfpenny in it, and boil it, and all the gold will fix itself to it.
XXXV. To gild paper on the edge.
1. Beat the white of an egg in three times its quantity of common water, and beat it till it is all come into a froth. Let it settle into water again, and lay a coat; of it on the edge of your paper.
2. Next, lay another of bol armenian and ammoniac salt, grinded with soap suds. Then pat the gold, and let it dry, before burnishing it.
XXXVI. To gild on vellum.
Mix some saffron in powder with garlick juice. Put two or three coats of this on the vellum, and let it dry a little, but not quite. Then breathing on the coat, apply the gold leaf with cotton; and, when dry, burnish it.
XXXVII. Another way.
Lay first a coat of ime and burnt ivory, grinded together with a weak isinglass water. Apply the gold on it; and, when dry, burnish it.
XXXVIII. Another way.
Grind and mix together four ounces of bol armeman. one of aloes, and two of starch; dilute it in water, and lay a coat of it on the vellum, then the gold immediately. When all is dry, burnish it.
XXXIX. A gilt without gold.
Take the juice from saffron flowers, in the season, or dry saffron in powder, with an equal quantity of yellow orpine well purified from its earthly particles. Grind all well together, and put it a-digesting in hot horse dung for the space of three weeks. At the end of that term you may use it to gild whatever you like.
XL. To gild without gold.
Open a hen's egg by one end, and get all out from the inside. Re-fill it again with chalidonia's juice and mercury; then stop it well with mastich, and put it under a hen which just begins to fet. When the time of hatching is come, the composition will be done, and fit for gilding.
XLI. To gild on calf and sheepskin.
Wet the leather with whites of eggs. When dry, rub it with your hand, and a little olive oil; then put the gold leaf, and apply the hot iron on it. Whatever the hot iron mall not have touched will go off by brushing.
XLII. Gold and filler in shell.
1. Take saltpetre, gum arabic, and gold leaves, and wash them all together in common water. The gold will sink to the bottom, whence pouring the water off you may then put it in the shell.
2 The silver is worked in the same manner, except the saltpetre, instead of which you put white salt.
XLIII. To gild marble.
Grind the finest bol armenian you can find with lintseed or nut oil. Of this you lay a coat on the marble, as a kind of gold size. When this is neither too fresh, nor too dry, apply the gold; and, when thoroughly dry, burnish it.
XLIV. To apply gold on glazed wares, chrystal, glass, china, &c.
Take a penny-worth of lintseed oil, and as much of, gold litharage; a halfpenny worth of umber, and as much of ceruse. Grind all together on marble; and, witn a little hair pencil, dipped into the said colour, dravy whatever you will on tlie above-mentioned wares. As soon as dry, lay your gold on it with cotton, which you pass along your check before taking the gold with it. And as soon as this is perfectly dry burnish it.
XLV. Mayt gold in oil.
Take yellow ocher, a little umber, white and black lead, which grind all together with greasy oil, and use it when necessary.
XLVI. To dye any metal, or stone, gold colour, without gold.
Grind together into a subtile powder ammoniac salt, white vitriol, saltpetre, and verdigrise. Cover the metal, or stone you want to dye, all over with this powder. Set it, thus covered, on the fire, and let it be there a full hour; then, taking it out, plunge it in chamber lye.
XLVII. To whiten copper.
Take one ounce of zinc, one drachm and a third part of it of sublimed mercury. Grind all into powder, then rub with it what you want to whiten.
XLVII. To whiten silver without the assistance of fire.
Take Mons-martirum's talo, which you calcine well in an oven till it can be pulverised. Sift it very fine. Then dipping a piece of cloth or stuff in it, rub the silver with it.
XLIX. To whiten iron like silver.
Mix ammoniac fall's powder, and quick lime, in cold water. Then make your iron red-hot several times, and, each time, plunge it in that dissolution. It will turn as white as silver.
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