as Obje£is of the Art ofByingy iBc. 367 



The former are more eafily managed, cheaper, 

 and more brilliant ; but the latter make amends 

 for their other defefls by their folidity and per- 

 manency. 



The colouring matter itfelf is formed, per- 

 haps, in a great meafure, of the inflammable, 

 ffl^ in fome cafes, united to the aftringenr, 

 principle. The identity of light and phlo^ 

 gifton, or, at leafb, that the one is a modifi- 

 cation of the other appears to be pretty clearly 

 proved. Plants, totally excluded from the fun's 

 light, acquire no colour; and flowers are ob- 

 ferved, cateris paribus, to pofl*efs the moft beau- 

 tiful tints, in thofe climates where they enjoy the 

 influence of that luminary, the moft liberally. 

 This matter therefore muft of itfelf be very fu- 

 gitive, and as phlogiftic bodies adl on, and 

 difiblve, each other, very powerfully, we are 

 hence enabled to account for the deftruftive 

 eff^e(5ts of folar light, on colour, when applied 

 to the dead fibre, from its dilTolving the phlo- 

 gifton, in the fame manner, according to Mr. 

 Delaval, as fpirit of wine difl^olves camphor.* 



The acids alfo ad on, and dettroy, colouring 

 matter, in proportion to their attradion for 

 phlogifton. Thus nitrous acid is highly and in- 

 ftantaneoufly deftrudive to many colours : but 

 is exceeded, in power, by the dephlogifticated 

 marine acid. This very adive fubftance is the 

 ftrongeft tcft of all others for the goodnefs of 



dyes 



* Mapchefler Memoirs, vol. II. 



