in Porcelain Painting. 137 



substance it may be cast in moulds, while the volatile metal 

 employed as a flux may be again driven oft'bv heat, so that 

 the cast platina may then be hammered like any other me- 

 tal. By employing this method, first mads known Ijy mv 

 worthy colleague iM. Achard, vessels and articles of various 

 kinds are made ot'platuia, and particularly at Paris. 



Bergman, however, had shown that platina which could 

 be reduced to a state of fusion only by employing a lart-a 

 burnmg mirror, might be fused also bv means of o.w fjeii 

 cas. In this manner M. Pelletier, by means of phosphoric 

 glass, made from bones, combined with charcoal powder, 

 brought large masses of platina to a state of complete 

 fusion. 



How far platina might be employed in porcelain painting 

 has never yet, as far as I know, "been examined : I there- 

 fore thought it of considerable importance to make scmio 

 experiments on this subject, which did not deceive my ex- 

 pectation ; but, on the contrary, convinced me that this 

 object, in the hands of an ingenious artist, may be brought 

 to perfection. 



Gold and silver have hitherto been the only metals sus- 

 ceptible of being employed in their metallic form in paint- 

 ing and ornamenting porcelain, glass, and enamel, (ioid 

 answers this purpose so completely, that nothing furtiicr 

 can bo wished for on this head; whereas silver does not 

 answer so well. As it possesses less density and is mor^ 

 porous than gold, it docs not cover the ground so completelv 

 V hen applied to porcelain in thin leaves. The second cause 

 pf the inferiority of silver when employed in paintinc; on 

 porcelain arises from its nature, in conscqueixee of which, 

 v.hen exposed to sulphureous and other phlo(j,istic vapours, 

 it becomes tarnished, loses its metallic splendour, and at 

 length grows black. This inconvenience renders silver 

 unlit for being employed in tine porcelain painting, and 

 confines the application of metallic substances in this man- 

 lier to gold alone. 



Platina, in this respect, may be classed next to jjold ; 

 ;md by its white colour may supply the place of silver willi- 

 put possessing any of its faults. It is not only capable, on 

 account of its density and weight, in which it exceeds e;oid, 

 of covering the ground completely, without leaving any 

 perceptible interstices, as silver docs ; but it withstands like 

 gold all the variations of the atmosphere, as well as sulphu- 

 reous and other vapours. 



The process which I employ in the application of ])la)ina 

 ](0 painting on porccluiii is sini^^le and easy: it is as f(»l- 



lows: 



