Ari of Pai filing in Enamel. 447 



the discoveries of modern chemistry have afforded the ma- 

 terials to supply this long-sought desideratum. From three 

 of the metals which till lately were known but to chemists, 

 and which were regarded as curiosities only, namely, platinum, 

 uranium, and chromium, are already produced four of the 

 richest and most useful of the colours on the palette of the 

 painter in enamel. And doubtless we may look to this source 

 for the means for further improvement. Before the introduc- 

 tion of oxide of platinum a positive rich brown was unknown in 

 enamel* : this colour when produced by the mixture of others, 

 as was previously the practice, was liable to alteration by re- 

 peated fires, becoming more opake and meagre, and acquiring 

 somewhat the appearance of common brown clay. With 

 such a material how was it possible for an artist to obtain that 

 deep, rich, and juicy transparency which is so highly and justly 

 valued by every judge of painting, and which distinguishes the 

 works of the great masters both ancient and modern ? The 

 oxide of platinum on the contrary yields a beautiful, indestruc- 

 tible, and richly transparent enamel brown, which no intensity 

 or frequent application of the furnace can injure. 



Mr. Cooper observes f that with the black oxide of platinum 

 " we can now produce an enamel colour which preserves an 

 intense black in the lighter shades, and is, moreover, capable 

 of sustaining the most violent fire, without injury, which none 

 of the former colours [blacks] will bear, without change." On 

 this 1 must remark that I have made many experiments with 

 this oxide, but have never been able to produce with it an in- 

 tense black enamel colour. A black it certainly will produce, 

 but not of sufficient intensity to be useful to the painter. I have 

 a black of great intensity which is unchangeable in the fire, 

 and into the composition of which the black oxide of platinum 

 does not enter. I have exposed this colour to the heat of an 

 enamelling furnace about forty times without any apparent al- 

 teration of its tint or diminution of its intensity. 



Colours proper for painting in enamel are not to be pur- 

 chased : those sold for the purpose are adapted only for paint- 

 ing on china. I have devoted much time to their improve- 



purpose of painting in enamel from these receipts will assuredly find, to his 

 disappointment, that they are utterly useless. The statements made in books 

 upon vitrifiable colours are really unaccountable, and truly does M. Brong- 

 niart observe in his essay, that " it is very remarkable, that if the processes 

 described in these works were strictly followed, it would never be possible 

 to form the colours for which they pretend to give recipes ;" and M. Clouet 

 is justified in exclaiming as he does of the authors, " None of them say what 

 they ought respecting enamel." (Phil. Mag., First Series, vol. vii.p. 3.) 



* For this invaluable acquisition the enamel painter is indebted to the 

 late talented and indefatigable Mr. Muss. 



t Journal of the Royal Institution, vol. iii. p. 121. 



