Art of Painting in Enamel, 443 



of the hardest crown glass; also the difficulty of obtaining it 

 of any size, and free from cloudiness or opacity." These ob- 

 jections, I understand, apply equally to that which is made at 

 the present time* ; to which it may be added that the modern 

 ruby glass is inferior to the ancient in this respect also, that 

 while the latter, on being exposed to the heat of a glass kiln, 

 preserves its colour unimpaired, that of the former suffers 

 considerable injury by such exposure, in some cases becoming 

 almost black. The importance of this difference will be duly 

 estimated when it is considered that, in consequence, the 

 modern ruby cannot be painted upon, as the heat required to 

 fix the fresh colour would destroy the beauty of its original 

 appearance. To meet this difficulty the modern artist has 

 recourse to the following ingenious expedient. He paints 

 upon a piece of plain glass the tints and shadowy necessary 

 for blending the rich ruby glow with the other parts of his 

 picture, leaving those parts untouched where he wishes the 

 ruby to appear in undiminished brilliancy, and fixes the ruby 

 glass in the picture behind the painted piece. Thus in such 

 parts the window is " double-glazed." 



Your " Correspondent" says that " the material employed 

 by the old glass-makers to tinge their glass red was the 

 protoxide of copper ;" but it would appear from the ana- 

 lysis made by Mr. Cooper that the colouring material was 

 not copper alone, for he states that he obtained in the process 

 *' a copious precipitate of chloride of silver." 



It is generally believed, as stated also by the author of the 

 paper on " Glass-painting," that copper yields the green in 

 enamel-painting. This statement is true if it is confined to the 

 productions of those artists who practised painting in enamel 

 prior to the late Mr. Charles Muss. He employed, as I do, 

 the oxide of chromium to produce this colour, and discarded 

 copper altogether : in the composition of enamel colours, I en- 

 tirely reject also the use of iron and manganese. 



In the paper on Glass-painting now referred to, it is ob- 

 served that " the accounts to be found in various works re- 

 specting this curious art are by no means satisfactory or com- 

 plete :" this observation may be extended, without offering the 

 least violation to truth, to the equally curious and beautiful 

 art of Painting in Enamel. Writers on the subject of ena- 

 melling confound the art of painting in enamel, with those of 

 painting on glass and porcelain, although these three arts are 

 almost as dissimilar as their products, — a painted window, a 

 richly ornamented vase, and an enamel painting. 



Enamel is a substance having for its basis a white and per- 

 * Mr. Cooper's paper appeared in 1824. 

 3 L 2 



