Page:Cyclopaedia, Chambers - Volume 2.djvu/464

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POR

Porcelain, or purcelain, a <j e !i-

cate fort of Earthen- Ware, chiefly manufactured in China, and thence, alfo, call'd China, or China-Ware ; but brought into Europe from other Parts of the Eaft, efpe- cially Japan, Siam, Surat, and 'Perfia. See Pottees-

Scaliger, and Cardan, tho' generally of contrary Sen- timents, are yet agreed, that what the Romans call'd Vafa Myrrhina, which were firft: feen at Rome in 'Pompey's Triumph, and which afterwards became fo very precious ; were the fame with the "Porcelain of our Times. See

jilYRRHINE.

This may be true : But if the Opinion be only founded on 'Pliny's Defcription of thefe Veffels, one would rather take 'em for a kind of precious Stones, of a whitifh. Co- lour, but varioufly vein'd and variegated ; found in fome Parts of Perfia.

Be this as it will, 'tis certain both thofe Authors are miftaken, when they tell us, that Porcelain is made of Jigg and Oifter-Shells beaten fmall, and buried under ground for 80 or 100 Years. The Account we fhall here give, will put that out of queftion.

'Tis not known who was the Inventor of Porcelain ; the Chinefe Annals, which ufe to contain every thing in any wife memorable, are perfectly filent about it ; nor do we know much more of the Time of its Invention. Only, 'tis certain it mult have been before the beginning of the fifth Century: The Anmkof Feouldam relating, that from the fecond Year of the Reign of the Emperor fam, about the year of Chrift 441, the Workers in Porcelain of that Pro- vince had alone furnifh'd the Emperors therewith.

There is Porcelain mads in feveral Provinces of China ; particularly thofe of FouKien, Canton, and Kimtetcbim 5 but that of the lad is moft cfteem'd.

The Chinefe call the Porcelain, tfhski : The word 'porcelain is but little known there, except among a few Workmen and Merchants ; and feems derived from the portuguefe Porctllane, a Cup, or Porringer.

Porcelain makes a very curious Article in Commerce, andeven in Natural Hiftory. Its Manufacture has hitherto pafs'd for a Myftery in Europe : and that in fpite of all the Endeavours ol the Jefuit-Miflionaries to penetrate into the Secret. The Veil, however, is at length drawn ; and in a Letter of V.Entrecolles to F.Orry, from Jaotcheou, dated September the ill, 1712, and lately publifhed in French, the whole Procefs is defcribed in all its Circum- flances ; with an Extraft whereof we ftiall here gratify the curious Reader.

The Art of making Porcelain, or China-Ware ; from a Letter of F. d'Entrecblles, a Jefuit- Miffionary in China.

IntheManufaflureofCPorfete'/V, there are four effential things to be confider'd ; viz,. The Matter it is made of. The Art of forming the Veffels, and other Works. The Colours wherewith it is painted. And, laftly, the Baking, or giving it the proper degree of Fire. Each of which will make the Subject of a feveral Article.

Matter, whereof Porcelain, or China-Ware, is made.

There are two kinds of Earths, and as many kinds of Oils or Varniihcs ufed in the Compofition of 'Porcelain. 'Hie firft Earth, call'd Kaolin, is befet with glittering Cor- pufcles ; thefecond, call'd Petunfa, is a plain white, but exceedingly fine, and foft to the Touch. They are both found in Quarries twenty or thirty Leagues from Kimtet- chim, a City which produces the fineft Porcelain-Works in all China ; and hither thefe Earths, or rather Stones, are brought in an infinite Number of little Barks, inceffantly naffing up and down the River Joatcheou for that purpofe. The Petunfa's arc brought in form of Bricks ; having been focut out of the Quarries, where they are naturally Pieces of a very hard Rock. The white of the beft Petunfa is to border a little on green.

The firft Preparation of thefe Bricks, is to break and found 'em, firft into a coarfe Powder with Iron-Mallets ; then in Mortars withPcftles that have Stone-Heads, arm'd »ith Iron, and wrought cither with the Hand, or with Mills.

When the Powder is almoft rendcr'd impalpable, they throw it in a large Urn full of Water, ftirring it bristly about with an Iron Inltrumcnt. After the Water has relied a little while, they skim off from the Top a white Sub- ftance form'd there, ot the thiclnefsof four or five Fingers ; °nd difpofe of this Scum or Cream in another Veffel of Water. They then ftir again the Water of the firft Urn, and again skim it, and thus alternately till there remain nothing but the Gravel of the Petunfa's at bottom ; which they lay a-trelh under the Mill, for anew Powder.

As to thefecond Urn, wherein are put the Skimminoj of the firft ; when the Water is well fettled, and becon?e quite clear, they pour it off; and with the Sediment; col- lected at bottom in form of a Pafte, fill a kind of Moulds : whence, wbenalmoft dry, they take it out, andcutit into fquare Pieces,which are what they properly call Petunfa's ; referving 'em to be mix'd with the Kaolin in the Propor- tion hereafter aflign'd.

Thefe Squares are fold by the hundred, but 'tis very rare to meet with 'em un-falfify'd : The Workmen, who, like the reft of the Chinefe, are errant Knaves in their Dealings, ufually mixing Refufe along with 'em ; fo that they are' ufually obliged to purify 'em e'er they can be employ'd.

The Kaolin, which is the fecond Earth ufed in Porce- lain, is much foiter than the Petunfa, when dug out of the Quarry ; yet is it this, which, by its mixture with the other, gives the Strength and Firmnefs to the Work. B.En- trecolles obferves, that fome Englifb or "Dutch, having pro- cured fome "Petunfa's to be bought, privately ; upon their attempting to make 'Porcelain at their Return into their own Country, could not fucceed for want of taking Kaolin along with it. Which the Chinefe being apprifed of, faid, drolling, " That the Europeans were wonderful People to " go about to make a Body, whofe Flefh was to fuftain " iifelf without Bones."

The Mountains whence the Kaolin is dug, are cOver'd without-fide with a reddifh Earth ; the Mines are deep, and the Matter is found in Glebes, or Clods, like the Chalk in ours. The Author is of opinion, that the white Earth of Malta is not much different irom the Kaolin, except that it wants the filver'd Particles. The Preparation of Kaolin is the fame with that of the Petunfa's, except that the Matter beinglefs hard, lefs Labour is required.

The 0//or Varnifi, which makes the third Ingredient in 'Porcelain, is a whitifh, liquid Subftance, drawn from me hard Stone whereof the Petunfa's are form'd ; that which is whitcft, and whofe Stains are the greeneft, being always chofen for this purpofe.

The Manner of preparing the Oil, is thus : The 'Petun- fa's being wafli'd, undergo the fame Preparations as for making the Squares ; excepting that the Matter of the fecond Urn is not put in Moulds, but the fineft Part of it taken to compofe the Oil. To an hundred Pounds of this Matter they caft a Mineral Stone call'd Chekao, refembling our Alum : this Stone is firft heated red-hot, and thus re- duced in a Mortar into an impalpable Powder, and ferves to give the Oil a Confiftence ; which, however, is ftili to be kept liquid.

The Oil of Lime makes the fourth Ingredient 5 the Preparation whereof is much more tedious and circumftan- tial. They firft diffolvc large Pieces of quick Lime, and reduce it to a Powder by fprinkling Water on it ; on this Powder they lay a Couch of dry Fern, and on the Fern another of the flack'd Lime, and thus alternately, till they. have got a moderate Pile; which done, they fet fire to the Fern : the whole being confumed, they divide the Allies that remain on new Couches of dry Fern ; fetting 'em on fire as before. And this they repeat five or fix times fuc- cefltvely, or even more ; the Oil being ftill the better as the Ames are oftner burnt.

In the Ann^sofFeouldam 'tis faid, inftead of Fern they antiently ufed the Wood of a kind of Medlar-Tree ; and that 'twas this gave the antient Porcelains that admirable Hue, which the Moderns cannot come up to for want of that Wood. 'Tis certain, however, the Quality of the Fern and Lime contribute very much to the goodnefs of the Oil.

A Quantity of thefe Allies of Fern and Lime are now thrown into an Urn full of Water ; and to an hundred Pounds of Ailies is added a Pound of Chekao, which diffolves therein. The reft being performed after the fame manner as in preparing the Earth of the Petunfa's ; the Sediment found at the bottom of the fecond Urn, and which is to be kept liquid, is what they call the Oil of Lime ; which the Chinefe efteem as the Soul of the former Oil, and which gives the 'porcelain all its Luftre. This Oil is eafily fophifticatedby adding Water to increafe the Quantity ; adding at the fame time proportionably of the fame Chekao to maintain the Confiftence. Ten Mea- fures of Oil of "Petunfa ufually go to one of Lime. To have the Mixture juft, the two Oils Ihould, be equally thick.

Manner of forming the Veffels, and other Works of

Porcelain.

The firft thing is to purify the Petunfa and Kaolin ; which, for the firft, is done after the manner already defcribed in preparing the Squares. For the fecond, as its foftnefs makes it diffolvc eafily, 'tis fufficient, without breaking it, to plunge it in an Urn full of Water in an open Basket. Tho r 5 10 E Dregs.