AND OBSERVATIONS ON LAC. 5[ 



1 1. The lixivia of pure foda and of carbonate of foda com- Soda and its car- 

 pletely diflblve the different kinds of lac; and thefe folutions |^ ate diffol ve 

 exaclly refemble thofe formed by means of borax, excepting 



that they are deeper coloured. 



Rather lefs than - of carbonate of foda is required to 

 diflblve (hell lac; and this folution, when dried, is fooner 

 affected by damp or water than the folution prepared by 

 borax. 



12. Lixivium of pure or cauflic potafli fpeedily diflblves the Aifo potafh, 

 varieties of lac, and forms faponaceous folutions, ilmilar to 



that in which borax was employed, exclufive of the colour, 

 which is deeper, and more approaching to purple. 



Lixivium of carbonate of potafli extracts a great part of the and its carbon? 

 colouring matter, but does not form fo complete a folution ate * 

 of the entire fubftance of lac, as when pure potafli is em- 

 ployed. 



The above alkaline folutions, by repofe, afford the waxen 

 foap which has been mentioned ; and acids, being added to 

 thefe folutions, and to that formed by borax, precipitate the 

 lac in a flocculent flate, and of a yellow or buff colour, which 

 precipitate, when melted, becomes fimilar to the lac ori- 

 ginally employed. If however an alkaline folution of ihell 

 Jac (prepared, for inftance, with foda) be gradually dropped 

 into a fufficient quantity of muriatic acid diluted with an equal 

 portion of water, and nearly heated to the boiling point, and 

 if after boiling the whole for about one hour the coagulum. 

 be feparated, and the clear liquor be carefully laturated with 

 foda, and again made to boil, a (mail quantity of a flocculent 

 precipitate is obtained, which was found to be analogous to 

 precipitated vegetable gluten, combined with fome of the co- 

 louring extract. 



13. Pure ammonia, and carbonate of ammonia, readily act Ammonia a&a 

 upon the colouring matter of lac, but do not completely diflblve P art)al) y' 

 the entire fubftance. 



§11. 



Analytical Experiments on Stick, Seed, and Shell Lac. 

 Lac, placed on a red hot iron, contracts, melts, fmokes Produces of lac 

 much, and leaves a fpongy coal. Slow diftillation carried to dnifnation VC 

 the red heat, gave from flick lac, 1 . Water flightly acid, 10 ; Stick lac. " 

 E 2 2. Thick 



