of flicll lac. 



AND OBSERVATIONS ON LAC 55 



potafti ; and, being heated, a fecond precipitate of gluten was 

 obtained, which, when well dried, weighed 9 grains. 



The 500 grains of (hell lac thus yielded, Component parts 



Grs. 

 A. Extrad ... 2.50 



£ I Refin .... 454.50 



q I Vegetable gluten - - 14. 



E. Wax - - 20. 



491. 



The mode of analyfis adopted for the fhell lac, muft un- Advanta 8 eBof 

 doubtedly appear lefs fimple than that which was employed u f e( ^ 

 for feed and flick lac: but, upon the whole, it was attended 

 with advantages ; for the (hell lac being in fmall fragments, 

 and not in the fiate of a powder, considerably facilitated the 

 decantation of the folution in alcohol from the refiduum ; and 

 although, in this laft, a portion of the refin was protected from 

 the a6tion of the alcohol, by being enveloped in the gluten 

 and wax, yet, by the affiftance of acetic acid, the remainder 

 of the refin, as well as the whole of the gluten, were diffblved; 

 the wax was obtained in a pure fiate ; and a feparation of 

 the refin from the gluten was afterwards eafily effected, by 

 the method which has been defcribed. As therefore acetic 

 acid is capable of difTolving refin, gluten, and many other of 

 the vegetable principles, it certainly mav be regarded as a 

 very ufeful folvent, in the analyfis of bodies appertaining to 

 the vegetable kingdom. 



From the refults of the preceding analyfes it appears, that 

 the different kinds of lac confift of four fubftances, namely, 

 extract, refin, gluten, and wax, the feparate properties of 

 which (hall now be more fully confidered. 



(Vie Conclufwn in our next.) 



Galvanic 



