ENCAUSTIC PAINTING. 425 



metallic oxyds, melted with some vitrescent mixture, and ground 

 to extreme fineness. These are worked up with an essential oil 

 (that of spike is preferred, and next to it oil of lavender) to the 

 proper consistence of oil colours, anil are laid on with a very fine 

 hair brush. The es ential oil should be very pure, and ihe use of 

 this, rather than any fixed oil, is probably that the whole may eva. 

 porate completely in a moderate heat, and leave no carbonaceous 

 matter in contact with the colour when red hot, which mi^ht affect 

 its degree of oxidation, an;l ihnce the shade of colour which it is 

 intended to produce. As the colour of some vitrified metallic 

 oxyds (such as that of gold) will stand only at a very moderate 

 heat, v. hiNt others will bear, and even require, a higher tempera, 

 ture to he properly fixed, it forms a great part of the technical 

 skill of the artist to supply the different colours in proper order; 

 fixing tit st those shades which are produced by the colours that 

 will endure tin. highest heat, and finishing with those that demand 

 the least heat, i he outline of the design is first traced on the ena. 

 mel, ground and burnt in ; after which, the parts are filled up gra- 

 dually with repeated burnings, to the last and finest touches of the 

 tenderest e< amel. 



Transparent enamels are scarcely ever laid upon any other me. 

 tal than gold, on account of the discoloration produced by other 

 metals, as already explained. If, however, copper is the metal 

 used, it is first covered with a thin enamel coating, over which gold 

 leaf is laid and burnt in. so that, in fact, it is still this metal that is 

 the ba-is of the ornamental enamel. \Vi*h regard to the vast num. 

 ber of important minutiae in the selection and order of applying 

 the colours, the management of the fire, &c. &c. almost the whole 

 of what is known on this subject is confined to the practical artist, 

 nor could this knowledge, if obtained, interest the general reader. 



[Pantolog. Clouet. Kunckel. 



SECTION IV. 



Encaustic painting. 



We have already observed* that this is an art upon which the 

 ancients highly prided themselves : invented to fix by fire the co- 

 lours made use of by the artist, who employed wax to give them a 

 gloss, and preserve them from being injured by the air. 



Section 1, of the present Chapter. 



