Dictionarium polygraphicum. The way to make China, or fine Earthen-ware; how to Enamel, Paint, and Gild them.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol I.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
Porcelaine, China, or fine Earthen-ware, is enamell'd with our white stuff, which is already prescrib'd for metals; and its painting the same, and of such colours as we have proposed for enamels.

The custom of enamelling on earthen-ware is of greater antiquity than that on metals; for in the time of Porsenna, who generously undertook the restoration of Tarquin to the Roman government in the Consulate of Valer, Publicola and Horat. Pulvilius, ann. mund. 3444, five hundred and four years before the coming of Christ, or thereabouts, the practice of enameling on ware was used in the estates of that prince; and what gives us very good reason to believe this is the name Porcelane, which has an affinity to Porsenna, though alter'd by the corruption of time. So it is also call’d Fayence from Fayence in the duchy of Urbin, where in the time of Michael Angelo and Raphael Urbin, this art was practised.

And as the secrets of nature are daily more and more discover'd, so has time employ'd the invention of man to improve this, and make it more excellent, not only condescending to en amelling, but proceeding also to painting and pourtraying thereon several curiosities, to which at length are added the ornaments of gilding.

These pieces of ware are of a very general use over all the world, as for ornaments over chimney-pieces, on cabinets and tables, or boards. The choicest come to us from China, and next to them those done at st. Cloud and Rouen; but there are very good made in Holland, at Savonne in Italy, and several other places in France.

The painting and enamelling on these, is what we are properly obliged to take notice of in our art; however, we shall flightly touch upon the composition and moulding the ware, and for this we will prescribe fine and delicate methods sufficient enough to answer the satisfaction of such as employ themselves in this art, and of those persons whose curiosity leads them to enquire after things, whereof they are not already inform'd.

The furnace for making of CHINA must be large, with an opening proportion'd to the vessel you are to place therein; of these there are several sorts, but the most commodious must be made as follows.

You may shape this furnace round or square, but the square is best, because of the opening; it must be made of good brick, and such stuff as can mostly endure the fire, of what bigness you please, with three divisions; the lowest for ashes must be a foot high, that the air may be communicated through its opening to the fire; the middle story is for the fire, and must be underlaid with a very good grate, to separate it from the under story, with an opening for the fuel, and be vaulted above, about a foot in height. According to the size of your furnace, this vault must be made, like that of an oven, and have an hole in the middle, of the same shape as the furnace, round or square, and proportion'd to its bigness, through which the flame may transmit itself to the uppermost story, where the vessels are put to bake in; this last story is to be at least two foot high, and its opening fourteen or fifteen inches, to put and draw the vessels easily in and out; the top must be vaulted too with a round or square hole, and over that a funnel, for the conveniency of the flame and smoak which it draws out.

All the opening, especially to the two uppermost, must be of strong brick, or crucible earth, or rather of iron, well luted within side, which must shut and open easily, and be very exact and fit, that the fire may not suck in any cold air, which might break the vessels.

This furnace will serve also for many other uses, as to melt, reverberate, calcine, cement, and several sorts of work in the laboratory of chymistry; because in it all the degrees of fire may be found, by the help of the lower opening, and the funnel of the chimney.

You may also for baking your China, make use of the furnace hereafter describ'd, where we discourse of painting on glass, putting thereinto your vessel of crucible earth for baking the ware in, and then cover'd over with a vaulted coverlid, with a hole at top to let out the flame and smoke of the reverberatory fire; for this reason there will be no occasion in this sort of furnace for any other opening, because the baking of vessels with your ware, are put in at top before the coverlid is laid on, and so the fire circulates about it, and it becomes very red, whereby the China-ware is baked, as is done in baking of pipes.

To make the stuff for CHINA-WARE.

The composition for this must be very fine, because of the ware, and not such as is used for ordinary vessels, we will therefore prescribe the manner of making it, to prevent the unsuccessful attempts of such as may be ignorant.

For this you must take of shells of every sort which are white and transparent, grind them well on a marble, then searce and reduce them to an impalpable powder.

To make your paste of this powder, first dissolve an ounce of very white gum arabick in a pail of water; when 'tis well dissolv’d and mixt with the water, dissolve therein about a quarter as much quick lime as your powder weighs; then stir and mix it very well, and afterwards put in the powder and stir all together, and knead it as they do mortar. Of this stuff form your vessels, according to the different sorts you desire; let them half dry or more, in the air, before you polish them with your smooth instrument of copper or iron for that purpose, and so leave 'em until they dry thoroughly. Being very well smoothed and dried, glaze them over with your white enamel, prepared as hereafter directed, and so set them dry in the furnace to bake and finish; where having kept them a convenient time, let the fire go out of it self. When the furnace is cold, take 'em out and paint them, and put them in again to bake a second time, observing what directions have been already given concerning these matters; and when the fire is gone out, and the furnace cold, you have the ware in perfection ready to take out for use.

You may make your China-ware also of pure earth, let it not be red tho’, but white or gray; you may try the sufficiency of it after ’tis prepard, by baking some beforehand; and when it comes out of the furnace sound and uncracked, 'tis good and fit for your purpose.

The preparation consists in drying well, and reducing it to a very fine powder; then put it into fair water, wherein has been already dislolv’d a little gum arabick; but most of those that make it, employ only water without gum. After this, you make your dishes, set ’em to dry, polish, glaze, bake, paint, and finish them as before; all which, those who work at them know better than I can express it.

How to Enamel CHINA.

For this, take of the milk-white enamel, grind it very fine, as painters do their colours; put the powder afterwards into a glass cucurbit, pouring some aqua fortis thereon; let it digest a little to cleanse off its impurities, and become fine and transparent; then pour off the aqua-fortis, washing the powder in water over and over again; grind it af terwards with a little gum-water on your marble, and so glaze the vessels with it within and without; dry them in the air, and bake them as before in the furnace.

Or you may heat the vessels to a redness in the furnace, and melt the enamel: when it is in a perfect fusion, dip the smaller vessels therein, and pour of it on the larger, for they will take no more on them than will serve them; set them by turns in the furnace, stopping it very well to avoid the air; bake, cool your furnace, and finish them as before; then take out the dishes, paint and bake them over again, observing all the former directions.

To paint CHINA.
This is done as the enamel, but much more easily, the figures being only just dash'd over in comparison to them; however you must grind your colours with oil of spike on the marble, as has been already said, and so paint on the dishes story, landscape, or any other fancy: but you must never expect to have them so complete and handsome, as those painted on the enamel'd plates, because the former are finish'd standing, and so enlarge in length or breadth; whereas the other are done on flats, and lying; besides, the dishes are for the most part round, and not so easily painted, for if they could be as neatly done as the enamel, they would be excessively dear.

To Gild CHINA.
You must first grind some shade-earth on a marble, with linseed-oil, prepar'd as shall be shewn anon, with which trace out your figures, which must be two whole days a drying; after this, apply very thin leaf-gold, and with a sharp graver, shape the figures, and then put the dishes in an oven, as soon as the batch of bread is drawn out; let the heat be no greater than one's hand may endure, else the vessels would crack; leave them in it for two or three hours or more, if the oven be not too hot; you may else make use of your furnace, by giving it the same moderate degree of heat, as experienced persons are well acquainted with.

Another way.
This is much more handsome and lively, be sides that it can't be effaced; you may with it gild vessels entirely, or border, or give them any lustre you think convenient for ornament, and it will look as well as fine gold.
You must first wet over the places you would gild with gum water lightly, then apply your leaves, and so let them dry: this is enough for plain gilding; but if you would have it carved or figured, you must make use of a steel graver, and afterwards bath the gold with water, wherein borax has been dissolv’d, powdering it in the mean time with crystalline powder, or milk white enamel reduc’d to a very fine powder; then set the dish on a reverberatory fire to melt and be polish'd; thus you'll have as fine a piece of ware as can be.

The way to prepare Linseed-oil for Gilding of CHINA.
Take a Paris pint of linseed-oil in an earthen pot which will hold about two Paris pints; put this on a fire, and when it begins to boil, throw in twice the bigness of a small egg of gum arabick pulveriz'd; stir all well until it be dissolved; then put in an onion of an ordinary size, and the like weight of garlick cut small; when the oil boils well, and swells up by the force of the good fire which must be underneath, pour it out into another such pot, and so in and out of each pot to the other, until all be very well mixt; then put it on the fire again, adding half an egg-shell of powder of mastick, and stir it very well; as soon as it boils again, it will foam and have a great froth, which must be scumm'd off; and then take it off the fire, and brew the ingredients together, with the two pots as before; continue to do thus with it, or stir it on the fire, until it rise no more.
This done, take a very dry toast of white bread to take off the grease (the oil still boiling) and when you put in the toast, ou must at the same time put in some pin-dust; stir all together, and let it stand for twenty-four hours afterwards; strain the oil through a linen-cloth, in which is some very fine sand, the better to filtrate it, and take off the grease, and so you'll have it pure and clear, which bottle up for your use.
Or you may (both ways being good enough) first mix with the oil two ounces of gold litharge pulveriz'd, adding the gum arabick as soon as it begins to boil; and to purify it, let it filter through a linen-cloth full of sand, while its hot, into a glass bottle, wherein is already half an ounce of fine camphire powder, shaking the bottle very well until the oil be cold; after wards lay it in the sun for fifteen days, and it will be entirely purged, and the longer 'tis kept will be the better.

The imitation of CHINA or PORCELANE ware upon tea tables, tea-boards, &c. upon gold and silver grounds.
After the tables or other utensils have been prepared as directed, mark out the designs upon them, make ovals or rounds upon them in a good disposition, so as to be uniform, or well adapted to the design, that they may answer one another in a regular manner; then paste on some paper in proper places, and when the paper is dry, draw your designs upon them, and paint them with water colours; then with a brush lay gold or silver size, and when that is near dry, lay on leaf gold or silver; and when all is dry'd, varnish over with the strongest varnish, except only the ovals or circles of painting, for those must be done with the white varnish, which is so transparent, that all the painting will appear through it.
If you lay on a gold ground, or any colour darker than that, then let your painting be blue and white; or if it is silver or light ground, then use the most fiery colours in your paintings.

To take off the figure from any piece of CHINA-WARE, tho' the person has not been acquainted with drawing.
If there be upon a dish, plate, cup, &c. any figures that you like and would take off, you must lay a piece of oiled paper over them, fo as to hold the piece steady till you can trace out the lines of the figures; then lay the oily paper on a paper black'd on one side, and the black'd paper on a clean paper; then trace the lines with a pen or blunted point of a needle, till the lines are all impress'd on the white paper, and draw them over with a black lin'd pencil, and mark the shades where they separate from: the light parts of the colour, that so you may lay on your colours as you see them painted on the China-ware; then cut out the figures close to the out-lines, and fix them upon your ground of whiting and size, or size with ground chalk, with thick gum, arabick and water; and when they are quite dry, paint them, the lighter parts in water colour, and the shady parts with var nish mix'd with the darker colours; when these are dry, wash all over with the white varnish before the fire, but take care that it be not so nigh the fire as to make the varnish rise in blisters.
When the varnish is dry, lacker it again with the same var nish, and repeat this a third time; then scrape some tripoli very fine, and with a soft rag dipt in water, take up a little of the tripoli at a time, and polish it by gentle rubbing till it is smooth; then wash off the tripoli with a soft spunge and water, and them. wipe it off with a dry fine cloth; and when it is thoroughly dry, if it be a white varnish, clean it with whiting and oil; and if a black varnish, with lamp black and oil.
But the common way is to cut out prints, and paste them on such parts as is thought fit, and then to colour them with water colours, and to varnish them with white warnish.
This is an easy way of painting, because the shades of the prints, when you lay on a transparent water colour, will give the light and shade that colour to your purpose, without using a dark and light colour.

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