The art of glass shewing how to make all sorts of glass, crystal and enamel : likewise the making of pearls, precious stones, china and looking-glasses : to which is added, the method of painting on glass and enameling : also how to extract the colours from minerals, metals, herbs and flowers ... : illustrated with proper sculptures / written originally in French, by Mr. H. Blancourt, and now first translated into English ; with an appendix, containing exact instructions for making glass-eyes of all colours.

OF THE ART OF GLASS. (Book 9)

BOOK IX. Shewing the Method of Drawing all sorts of Story, or Fi∣gure, on Glass, in Paint, Gilding, Marbling, &c. (Book 9)

CHAP. CCI.

THE Art of Painting has been still so Noble and Excellent, that all those great Persons, who have practised it, were always distin∣guisht among the most eminent of their Age; those celebrated Pieces we have of it in our Days, to the Ornament and Admiration of all Europe, has setled so great a Veneration for their Memory, as will eter∣nize it to Posterity.

The Dorians, Corinthians, Ionians, and Romans, were the People that paid the most esteem to this No∣ble Art, for which they conceived so great Opinion and Delight, that they lookt upon the famous Pain∣ters of their Time as Demi-Gods, and ranged them among the first and most Learned Men in the World.

The Ancients did not only pay a Deference and Honour to the Nobility and Illustrious Birth of Great Men, but to their Worth and Vertue too: Hence the Athenians erected a Statue in Memory of Aesop, who was but a poor Slave: Would they have done it if this eminently Ingenious Fellow had not possessed so many excellent Parts? No, 'twas not for the sake of his Picture which was too deformed and ugly to please or Charm 'em, but to convince Posterity how the way to Glory is not shut up from the meanest Persons.

Can there be any thing more taking, or compleat, than the Natural Imitations which issue from Paint∣ing? Has Nature any thing more considerably admi∣rable? Do we not see her display'd in the Pourtraits of those Excellent Masters, who with so much Art and Delicacy have exprest all whatever she has pro∣duced in this sublunary inferiour Orb, so that 'tis not possible to see them without admiring, or to ad∣mire them without Astonishment.

What wonderful Fancies too have they drawn from the Superiour and Heavenly! They have so lively shewn the Rising and Setting Sun, Night and Day, the Face of Heaven sometimes Calm and Serene, and again darkned with Clouds, the Thunder Showers, Storms and Seas raging, with all their Wrecks, and in the Microcosm, or little World of Man, they have exprest his Joy, Sadness, Smiles, Tears, Pleasure, Dissatisfaction, Life and Death; in short, all the Alterations which Creatures are liable to, whereof the enumeration would be very tedious.

This fine Art, as well as that of Glass, does not lessen the quality of its Practitioners, the contrary whereof happens in all other Arts; for Princes, and many of our Monarchs, have granted the Privilege of Nobility to several Masters thereof, to intimate to Posterity the extraordinary Esteem they had for them, upon the Excellency of those Incomparable Pieces which their Pencils had produced.

Though painting on Glass be very ancient, 'tis yet much more modern than that of Painting on Wood, or Cloath, as being of no longer standing than this Art of Glass-work: The first who painted on Glass, did it only in Distemper; that is, in Co∣lours mixt with Glue, but this not abiding the In∣jury of Time, they invented the way of doing it with Fire-Proof Colours, which are incorporated with the Glass, by Baking and Melting them toge∣ther; and as soon as this Secret was discovered, eve∣ry Body took delight to practice the Draught of Fi∣gures, and entire Histories thereon for Ornaments, whereof we have still some remaining Pieces on old Church Glass; but those Figures before the Year 1500, had not half the sufficiency of Base, or Relief, as is required in Painting.

Those who would fain Work in handsome and lively Colours, made use of Glass-Frit, tinged in the Glass-house, as well for Carnation as Drapery, whereon they drew the first Lines of the Visage, and other Parts of the Body in Black, and so Shadowed 'em with Strokes and Dashes.

But Painting having since received an Improve∣ment in France, those Works became more perfect, and in so short a time with such advantage of making fair and most exquisite Pieces, as are even at this Day the Admiration of the Learned, of which, all the Honour must be ascribed to the French, who were

the first Discoverers of this great Perfection in the Art.

We might easily assign several ways of this Paint∣ing among the Ancients, but since they are out of Practice, and the latter Methods much more excel∣lent, we shall satisfie our selves in prescribing only such as may suffice, and gratifie the Curiosity of those who love this Art.

And not only the Method of Painting, but also how to prepare the Colours, to bake and finish 'em in the Furnace; of this we'll give a short Descripti∣on in the next Chapter; that Secret of ordering the Fire, which is the Life and principal Agent of all the Works, with that of Gilding, Marbling, &c. as will be shewn in the Sequel of this Book.

The most part of Ingredients useful for this Ser∣vice of Painting, will also tinge the Glass well enough, and we will make use of those mentioned elsewhere, to avoid useless Repetitions on the Subject.

CHAP. CCII. A Furnace for Painting the Glass, and Setling the Colours.

WE have mentioned this Furnace in Chap. 194. but did not take notice of its Form, or Ap∣purtenances, because the Business which obliges us to speak of it there, is very different from this.

This Furnace must be Square, of good Brick, two Foot high, and so much every way, and have three Divisions; the undermost for the Ashes, must be six Inches high, the middle one for the Fire must be six Inches high, and have its Opening five or six Inches broad, and four deep, with a good Iron-Grate,

[illustration]

and three square Bars of Iron across to sup∣port the Earthen-Stove hereafter described: The uppermost Division must be a Foot high, with a lit∣tle Opening about the middle before of four Inches high, and two wide, to put in and draw out the Ware a Baking, to see if it be well done.

In this uppermost Division must be put the afore∣said Stove of good Fire-proof Crucible Earth, the Bottom an Inch and half thick, and from thence up to the Brim ten Inches full; it must be square as the Furnace, and have two Inches room from on all sides, that the Fire may flame round about it to Bake the Work, and therefore placed exactly in the middle of the Furnace; there must be also in the Fire-part of this Stove, an Opening just against, and of the same Size and Form as that of the Furnace, for the conveniency of putting the Ware in and out.

Take this Method of distinguishing the Furnace in all its parts, and to lay down a clearer description thereof, observe,

The Letter A is the Ash-hole for the Ashes that fall from above through the Iron-Grate; and note, That the wider the Opening is, the more violent will the Fire be.

The Letter B is the Fire-place.

The Letters C are three Square Iron-Bars to sup∣port the Pan for the Ware.

The Letter D is the Opening of the Furnace and Pan, through which the Ware must be conveyed in and out.

The Letter E is the Earthen Pan, wherein all the Painted-Ware must be Baked.

The Letters F are two half Lids of Potters Earth for covering the whole Furnace above: As soon as the Stove is full of Ware, they must be well closed and luted together, to prevent the Air coming in any where but by the four square holes at both ends of the

Lid, and the two Semicircles in the middle, which make a round Hole for a Chimney; when the two half Lids are closed, those five Holes are for letting out the Smoak and Flame of the Furnace.

CHAP. CCIII. To make White-Ground for Painting on Glass.

NOW to pursue our Work, we will begin with the Preparation of all the Colours to be used in Painting Glass; for before we proceed to pre∣scribe the Rules, how to work the Materials must first be considered.

The White is compounded of several Ingredi∣ents: The first are small White River Peble-Stones heated red over a Fire, in an Iron-Ladle, and thrown afterwards into an Earthen-Dish full of cold Water to calcine them, and this must be repeated several times, until they be prepared; afterwards being dried, pound them with a Stone, or Glass-Pestle in a Stone-Morter, and so grind them upon a Marble to an impalpable Powder; then mix a fourth part of Nitre with it, and calcine them in a Crucible; then pound and grind them again, and calcine them a third time over a smaller Fire than your former, and so take them off for Use.

This done, when you would Paint with it, add equal parts in weight of Gip, a sort of Talc found among Plaster-mold baked on the Coals to a White∣ness, and reducible to Powder, and Rocaille, where∣of we have already spoken, grind them all three very well together in a hollow Plate of Copper, with Gum-Arabick Water; thus have you your White in good condition to Paint withal.

CHAP. CCIV. To prepare Black for painting on Glass.

AS this Colour cannot be omitted in any sort of Painting, so in this; the manner of using it is much the same, and the Preparation easie. You must grind Scales of Iron from the Smith's Anvil-Block, for three Hours on the shallow Copper-Bason, or Plate; add to this one third of the same weight of Rocaille, with a little Calx of Copper, to hinder the Iron from turning Red in the Fire; grind it to as impalpable a Powder as you can bring it to, and so keep it in a close Vessel for use.

CHAP. CCV. To prepare a Yellow Paint for Glass.

THIS Colour requires a more costly Preparation than the precedent, because it cannot be well done without a tenth part of prepared Silver, as we shall shew hereafter.

Take fine Silver in Plates from the Copple, stra∣tifie 'em in a Crucible, with Powder of Sulphur, or Nitre, the first and last Lay being of the Powder, and so calcine them in a Furnace; this done, cast it out, as soon as all the Sulphur is consumed, into an Earthen-Bason of Water, and afterwards pound it in your Stone-Mortar until 'tis fit for the Marble, and so grind it with some of its Water wherein it was cooled, for six Hours; then add nine times

its weight of Red-Oaker, and grind them together for a full Hour, and 'tis done and fit for Painting on Glass.

CHAP. CCVI. To make a Blue for painting Glass.

THE whole Secret of this Preparation, depends on the calcining the Ingredients, and goodness of the Crucible: Take two Ounces of Zaffer, two Ounces of Minium, and eight Ounces of very fine White Sand; put all these into a Bell-metal Mortar, and pound them very well, and so into a Crucible covered and luted over a quick Fire for an Hour; then draw off the Crucible, and pound them again as before: This done, add a fourth of its weight in Salt-peter powdered, and having mixed all very well together, return them into a Crucible covered and luted, which place again in the Furnace for two Hours at least, continuing such another Fire as the former: The Crucible being off and cool'd a second time, grind the Mass as before, and so put it into a Crucible again, with a sixth part of Salt-petre, and let it remain on the Fire for three Hours; then take off the Crucible, and immediately with an Iron-Spa∣tula red hot, take out the Matter lest it should stick, being very clammy and hard to be emptied.

'Tis convenient to have strong Crucibles for this Calcination, because it remains so considerable a while in the Fire, and they must be luted with an extraordinary lute; you may use that we have given directions for in Chap. 109. adding Powder of Borax, to the Powder of Glass vitrified, which helps the Fusion of the Glass, which we have omitted there;

but the greatest stress lies in Baking the Crucible af∣terwards in a small Fire, to cement the Pores, and make the Earth compact as Glass, which would be very much furthered, if you threw on it a considera∣ble quantity of Salt as it comes out of the Fire, this would glaze it, and capacitate it for retaining the Spirits in the Fire.

CHAP. CCVII. To make Red Colour for Glass Paint.

THIS requires as much caution as the Blue: You must take Scales of Iron, and Litharge of Silver, of each a Dram, Feretto of Spain half a Dram, Rocaille three Drams and half; grind all these for half an Hour on a shallow Copper-Plate, in the mean time pound three Drams of Blood-Stone in an Iron-Mor∣tar, and add it to the rest; then pound a Dram of Gum-Arabick in that Mortar to an impalpable Pow∣der, to take off the remains of your Blood-stone, and so add it to the rest, grinding them still continually, lest the Blood-stone be spoiled.

The best manner of grinding these is to pour Wa∣ter by little and little on the Ingredients as you grind them, neither wetting them too much, nor too lit∣tle, but just as much as will keep a good Temper as for Painting: Afterwards put all into a foot Glass, and so drop on it through a small hollow Cane of Wood, or with your Finger, as much Water as will bring it to the consistence of an Eggs-Yolk buttered, or a little more, then cover the Glass to preserve it from Dust, and so let it stand three Days to settle. After this, decant the clearest and purest of the Co∣lours that rise at top, into another Glass, without

disturbing the Sediment; and two Days after it has settled anew, pour off again the purest of the Colours as before. This done, set it in the Body of a broken Matrass, or Bolt-head, over a gentle flow Fire, to dry easily, and so keep it for use.

When you have occasion for it, take a little fair Water in a Glass, and with it moisten as much Co∣lour as you think convenient, that will be excellent for Carnation; as for the Faeces, which are very thick, dry 'em too, and you may moisten these in like man∣ner with Water for Drapery, Timber-colour, and such other as you think convenient.

CHAP. CCVIII. To make a Purple-colour for painting of Glass.

THE Preparation of this Purple-colour, is ex∣actly like that of the Blue, for this Reason we need not use any tedious Repetitions: You must take an Ounce of Zaffer, and an Ounce of very pure and clean Perigeux, two Ounces of Minium, eight Oun∣ces of very fine white Sand, pound all these in a Bell∣metal Mortar, and reduce it to an impalpable Pow∣der; put it afterwards into a good Crucible well covered and luted, in the Furnace; keep a very good Fire to it for an Hour, then draw it out, and as soon as it is cold, pound the Mass over again in the same Mortar; to this add a fourth part of its weight of Nitre, mix them together, and put them into the Crucible, and so proceed as directed in Chap. 206. until you have a fine Purple-colour.

CHAP. CCIX. To make a Green Paint for Glass.

THE Change of the Ingredients makes this Colour, but the Method for incorporating them is the same as the former: Take two Ounces of Aes ustum, of Chap. 35. to this add two Ounces of Minium, and eight Ounces of very fine white Sand, pound these together in a Metal Mortar to an impalpable Powder, and put it afterwards in a Cru∣cible luted and covered into a Wind-Furnace, giving it a good Fire for an Hour; after this draw it off, and let it cool, then pound it again, adding a fourth part its weight of Nitre in Powder, grind and mix them well together, putting them afterwards into the Crucible, luted and covered, in the Furnace, for two Hours, and so forth as in Chap. 206. Thus you'll have a very fine Green.

CHAP. CCX. Of other Colours in general for Painting on Glass.

WE have directed how to make the first Master∣Colours for Painting on Glass; now we proceed to shew what other depends on them with∣out enlarging on these Preparations.

The Red in Chap. 207, serve for Carnation, but there ought to be one part of Feretto of Spain, as in Chap. 21. in the Composition, and another of Rocaille,

of which we will give the Preparation in the next Chapter; grind these on your Copper Plate, imbi∣bing the Powder with Gum'd Water, until it be made fit for use.

The Red Faeces there also mentioned will serve in Drapery, and to describe Timber-work, Trunks of Trees, Hair, Brick, and such other things; you must take an Ounce of Feretto of Spain in Chap. 21. as in the former Composition, an Ounce of Iron-Scales, two Ounces of Rocaille, grind them well together up∣on the Copper-Plate, moistening them with Gum∣Water, till they be brought to the proper consistence, neither too thick nor too thin, so you'll have a Red inclining to a dark Yellow, very fit for use.

There be several more made use of in this, as well as in other Painting, but are compounded of the prin∣cipal Colours, as we have intimated in our Discourse of Colours for Painting on Enamel, in Chap. 186.

CHAP. CCXI. The Way to make Rocaille.

ALL Haberdashers of Small-Ware, sell this Ro∣caille, which are Green and Yellow Grains, whereof they make Beads, and sell them to the Coun∣try People; much also of these Trangums are ex∣ported to the Indies, to Africa, and the adjacent pla∣ces, where the Inhabitants wear 'em about their Necks, and on their Scarfs, Bracelets and Wast∣belts.

It is used also in Painting on Enamel and Glass, veryfrequently, though ill qualified and full of im∣pure Lead. We have already taken notice of this before, and tho to avoid this they make choice of the

most clear and transparent Rocaille, and such as is least charged with Colour, yet still 'tis very far from being sufficient; 'tis true, it contains less Lead, how∣ever even that which still remains is likewise impure, and not at all purified.

We have directed such as work in Enamel, and we cannot avoid it also here to advise you instead of Rocaille, to make use of our Crystalline Matter made with Saturnus Glorificatus, Chap. 112. or such other∣like Ingredients, as we have prescribed, which are perfectly cleansed; however to please every Body, we will give a Preparation of this Rocaille, and how to compound it, which is very easily done: Thus,

To make the Yellow Grains, you must take a Pound of fine white Sand, three Pound of Minium, mix and pound them together very well in a Mortar, and put the whole into a strong Crucible covered and luted, dry the lute, and put it afterwards into the Glass-house, or Wind-Furnace, where the Fire is violent, to reduce this Matter into Glass, as that of Saturn, made in Chap. 82. having thus finished the Rocaille, make it up into Grains, or any other Shape you please.

The Way of making the Green, is quite contrary to that of the Yellow: Put three Pound of fine white Sand to every Pound of Minium, and it will be very compact. This Stu•••• will alter its Colour, and become a pale Red in melting; and these are the Compositions and way of making this Rocaille, which most Workmen use: Thus you see there can be no preparing it without Lead, which makes it so full of Impurity.

CHAP. CCXII. The Way to Paint on Glass.

THE Painting on Glass is of such fine Effect, as becomes the Admiration of the Learned in all Noble Arts: Nothing can be more wonderful to the Sight; besides, its continuance, and resisting all the Efforts of every Season, and badness of Weather, for several Ages, tho this last Excellency was un∣known to the first Practitioners, and reserved for this latter Age, however the Honour is due to them, since they made the first Secrets and Discoveries in this Art, and 'tis much easier to improve, than form a new Invention.

If Glass were malleable, and discharged of its Na∣tural Frangibility, nothing could equal the Paint thereon; 'tis not to be tarnished, but always main∣tains its primitive Beauty and Splendour, without any obstruction to the Transition of Light; and there may as fine Fancy be done on it, as on Limn∣ing, there would certainly be nothing on Earth so rich or precious as Glass, whether Painted, or Tin∣ged, if it had this principal Perfection of Malleabi∣lity, which many Learned Men have studied for, and daily find; but such is the Corruption of this Sinful Covetous Age, that those Wise Seniors of this Art, do rather chuse to pass for Ignoramus's, than run the Risque of Perpetual Confinement, by exposing so fine and delicate a Secret, which would incur the Envy of the Great: and this they take care wisely to avoid.

We have already taken notice that such as for∣merly Painted on Glass, were both Painters and

Glass-makers, and that such Gentlemen as were of them, received neither lessening in Birth nor Quality, as in case of other Arts, for this Prejudice is exemp∣ted in the Art of Glass, and our Kings have that E∣steem for the Curious therein, that they have grant∣ed them such ample Privileges.

Now to proceed to the Manner of Painting on Glass, which is the Subject of this Chapter, where∣in are several Particulars to be considered, which we will endeavour to distinguish as well as possible.

First choose such Glass as is usually called Glass of Lorrain, tho there be such and as good made at Ne∣vers; for this sort of Glass receives the Colours bet∣ter than any other, because 'tis best compact and a∣ble to resist the Fire; 'tis very easily known; 'tis not altogether White, but of a Whitish Yellow. But to proceed.

You must have the Original you Paint by, ready drawn and proportioned, on strong Cap-Paper, in all its Colours and Perfection; for your better advan∣tage in Pattern, lay it on a Table, and so choose your Pieces of Glass to be Painted, and take care to fit them so to each other, as they may joyn easily after∣wards without any prejudice to the Draught from displacing them, and so confounding the Figures and Pourtraits, or from the Lead which must joyn them afterwards, by obscuring any parts of the painting; then mark out each piece on the Tablet, by No. 1, 2, 3. for better distinction, and so trace them over with the Black given in Chap. 204. with a Pencil, as we shall further shew; do this very exactly, neither too slightly nor too thick, and so let it stand two Days to dry, before you paint it.

Then having all your Colours in readiness, so as directed in the foregoing Chapters, fill your Pieces off with Colours, for which use the Nib of the Pen∣cil, especially in Carnation, where you must be very

exact; you must also be very Circumspect and Expe∣ditions, and take a great deal of care not to blot or blur the Tracings, and chose rather to paint on the other side of the Glass.

All the Colours, except Yellow, may be applied on the same side, and that you must do on the con∣trary side, because it is apt to mingle with the other Colours, and if near the Blue, will compose a Green; so that for want of such precaution the whole Work may be spoil'd; if the Yellow transmit it self perfectly through the Quarre, it is as well as if it had been done on the same side; and take notice by the Way, that the other Colours have not so ready a Transition, because they consist of a Grosser Body.

The Yellow ought to be very equally and justly laid on in a greater or lesser quantity, as you'd have your Shadows; observe this too in the rest, especi∣ally to lay them on as quick as possible, as we have already said, particularly the Azure, Green, and Purple require the most exactness of any.

Now to set off and heighten the Lights, in piling a Beard, describing Hair in Drapery, or otherwise, use the Handle, or But-end of the Pencil, a small pointed Stick, or Quill, wherewith take off the Co∣lours in those places you would Enlighten, which is easily done.

Such Works as are done in Grisaille you must paint after this manner: Trace your Piece with Black, and let it dry for two Days entirely, do it over very lightly and equally with a Wash so thin laid on, as not to efface the first Lines, and let it dry for two Days; after this run it over again with the same Wash where you find it convenient to give a se∣cond Tinge, and let it dry two Days longer: Then to give it the Lights; and convenient Heightnings, take the sharp But-end of your Pencil, or pointed

Stick, or Pen, as before, and take off the Colour of the first Wash, in the most necessary places, and so your Work will be finished.

To make this Wash is easie: Take a small Pewter Cup, or other Vessel, and put therein a quantity of black colouring, then dissolve Gum-Arabick pow∣dered in its weight of Wine, and throw this on the Black in the Pewter-dish, or Saucer, that it may be very clear, and not easily dry'd, and that you may have your Wash for painting Glass in Grisaille, or Gray.

CHAP. CCXIII. How to order your Glass in the Furnace after Painting, and to manage the Fire.

AFTER your Glass is fully painted, and the Draughts perfectly finished, the difficulty will be to Bake the pieces, so as to give it a consistency with the Glass, by penetration, which may be thus done. You must work with the Furnace mentioned in Chap. 202. and its Stove of good Crucible Earth, to contain all the Work, which must be stratified on this manner.

Take good Quick-lime well digested, searced, and finely pulverized; and for the better security let it digest thrice in a Potter's Furnace, and so powder and searce it; then make a very even lay thereof, a∣bout half an Inch thick, on the bottom of your Stove, and then a lay of pieces of broken Glass, and afterwards another lay of Powder, and so another of Glass, then another of Powder; the reason of ma∣king this Stratification of powder and old Glass, is to prevent any injury from the violence of the Fire,

which will be very smart under the Stove; this done upon the third Bed of powder, lay a lay of painted Glass, and so continue S.S.S. each lay of powder and Glass being equally or evenly made, untill all the pieces of paint are put in, or the Stove full, and upon the last lay of Glass lay the uppermost of pow∣der somewhat thicker than the former; then cover the Furnace with its Shrowds of Earth, joyning and luting them well together, all round with the best lute, so that it may admit of no respiration, but through the fire holes, or the Opening of the Fur∣nace, whilst you draw out the proofs or Tryals you make, as we have hinted elsewhere.

Your Furnace being thus ordered, and the lute dry'd very well, begin to heat it gently with some Charcoal on the outside of the Furnace, at the en∣••rance, and so by degrees, and very leisurely im∣proving it, lest the Glass should be broken, or the paint spoil'd; continue thus for two Hours, then thrust the Fire in further, and let it remain there for an Hour, putting it in by little and little under the Stove, where leave it for two Hours longer, then increase the Fire by degrees for two Hours, and so continue to apply Fuel until the Furnace be full of Charcoal, and you perceive the Flame convey its self through every hole of the Cover; keep it thus very violent for three or four hours, shutting the Door of the Furnace; you must be very cautious and circumspect, during the whole Work, from the first two hours that the Fire remains at the En∣trance.

Observe from time to time to draw forth your Tryals, or pieces of proof in your Stove, to see if the Colours be melted and the Yellow qualified, you may perceive how the Work goes on by the spark∣ling of the Iron-bars under the Stove.

As soon as you find your Colours almost done, im∣prove the Fire with some very small Billets of dry Wood, they must be very little for ease in putting them in, and to prevent Smoaking, and to make the Flame environ and reverberate over and round about the Stove, which must be continued until you have finished, this will be in twelve or fourteen hours; then let the Fire go out and the Work cool of its self, and so take it out, and 'twill be finished.

CHAP. CCXIV. Another Way to Paint on Glass.

THO the former way be very fine and lasting as can be, yet we will here shew another more easie, and altogether as effectual.

Take very White Glass, varnish it very thin on one side with a White Varnish, then having before made choice of some fine Impress, or Cut, on Paper, just fit for the piece of Glass you design to paint its Fancy on, dip it in Water, and letting it soak and dry a little, clap the Picture-side thereof to the Var∣nish-side of the Glass, as exactly, plain, and evenly as possible, and so let it dry throughly; afterwards moisten the Paper on the Blank-side, and with a blunt Graver draw off and trace the Lines of the Picture, which will afterward remain perfect and distinctly on the Varnish-side of your Glass Quarre.

This Draught is for the Model you must paint your Fillings in, and observe that the Tracings and Strokes of the Picture are to serve you in Shadow∣ing, which cannot be rejected without disadvantage to your piece.

The manner of painting on Glass, is quite con∣trary to that of Limning, or Painting on Cloath, or Wood; for in this the paint being but on one side, is plainly visible on the other; here the Settings off are first done, then the compound Colours just run over, and so continuing until perfected; whereas on Linen, &c. the Settings-off, or Heightnings, are the last strokes, and their Ground-colour, or first, is that which we end withal, and make our last lay with in all pieces done on Glass.

We do not shew the Way to make up the Colours, nor how to mix and finish the Artificial ones, for that relates immediately to the Art of Painting, of which se∣veral pieces are extant, and not to this Art of Glass; and these noted herein are the same as in the other Art of Painting on Cloath, and not very uneasily pre∣pared.

You must also paint on Glass, just as in Miniature, with Water-Colours, laying your Picture under∣neath it, as before, and this will shew finer than if done in Oyl; besides, the Colours dry in a mo∣ment.

Your pieces being thus done in Oyl, or Water∣colour, may receive a very additional and improving Beauty, by over-laying all the Colours, except the Ground, with Leaf-Silver, which will appear very glorious and lively on such as are transparent; to wit, Lakes, Verditers, &c.

CHAP. CCXV. The Manner of Gilding on Glass.

WE promised to shew this Way of Gilding on Glass after we had done with Painting, and this we will discharge here.

Take any Glass you please, and moistening it over where you design to gild, with Gum-Water, apply your Leaf-Gold, and so let it dry; cover the Glass over with any piece of hollow Glass, and set it on an Iron-Plate at the Mouth of the Furnace to heat gen∣tly, and when 'tis well heated, move it in further, and in a very little time it will be red hot; then with∣draw it, and let it cool slowly at the Furnace Mouth. Thus if you have laid your Gold well on at first, you'll find it so well communicated to the Glass, that 'tis impossible for any Tryal to endamage the Gilding.

And after this method you may do with Globes, and give them a wonderful Beauty, which no Dust, nor injury of Time can alter.

CHAP. CCXVI. Another Way to Gild Glass.

THIS second Way is altogether as fine as the o∣ther; besides, the Gilding is better coated, and less exposed to Injury.

Take a Glass and moisten it every where, you design to Gild, with Gum-Water, and lay on

your Leaf-Gold, letting it dry; this done, run the Gold over with Water wherein Borax has been dis∣solved, and so dust it with impalpable powder of Glass; set it afterwards by degrees into your Fur∣nace, until it become red hot, and the powder on the Gilding be melted and run; then draw it out leisure∣ly, letting it cool at the Mouth of the Furnace, and you'll have your Glass very finely Gilded, so that nothing in Nature can spoil it, unless it be broken.

Or you may Gild on Glass with Linseed-Oyl, &c. as in Chap. 198. after the same manner as on China, but the Ways we have just now given, are so fine, that we look upon them to be more excellent; such as would make a choice may work by Directions in this present Chapter.

CHAP. CCXVII. To imitate Precious-Stones in Colours, on Globes, or other Vessels of White Glass.

THIS Way of tinging is different from what we have already given; and because we would not willingly leave out any thing that may serve the Cu∣rious, we will give the Method in this Chapter.

You may thus tinge any Vessel of White Glass either Globular, or Concave, with Mouth-Glue, let∣ting it soak in Water for two Days, and so boil it af∣terwards until it be all melted, and let it cool •• little.

Pour it Milk-warm into your Globe, or other Ves∣sel, shaking it therein to wet it all over, and so pou•• it out again: Then your Colours being all ready i•• Powders, first blow in the Vermillion through 〈◊〉〈◊〉 hollow Pipe, so as to represent Clouds or Wavings

in like manner blow in the Blue-Enamel, Scales of Copper, Orpiment, and Lake, all in fine powder; these Colours will stick in Undulations, because the Glew is moist; you may do thus with any other Colours: This done, take Plaister well pulverized, and put a good quantity thereof into the Vessel, and shake it well all over before (and until) the Glew be quite dry, and it will stick all round, then shake out what remains loose, and you'll have the outside fine∣ly party-colour'd and Marbled, &c.

When these Colours are well dried, they will stick so to the inside, that they will never come off, but remain always fine; set these Globes on Stands where they may be for Ornament, and the pleasure of those who shall see and consider their Admirable Beauty.

The End of the Ninth BOOK.