18- Experiments avd Ohscrvalions on Lac, 



If the pieces of shell lac, after cligcstion in alcohoi, be 

 treated with alkaline lixivia, then the whole is dissolved, 

 and forms a turbid solution. But when acids are employed, 

 the chief part of the gluten is alone acted upon, and a con- 

 siderable residuum is left, consisting of the wax, some of 

 the resin, and a portion of gluten, which has been protected 

 from the action of the acid bv the two former substances. 



The abavc properties indicate a great resemblance between 

 this substance and the gluten oF wheat ; I therefore have 

 called it glutin, but at a future time I intend to subject it 

 to a more accurate examination. 



Properties of' the JVux of Lae. 



If shell lac be long and repeatedly digested in boiling 

 nitric acid, the whole is dissolved, excepting the wax, which 

 floats on the surface of the hqiior, like oil, and, when cold^ 

 may be collected ; or it may be more casiK- obtained in a 

 pure state, by digestin-g iht residuum left by alcohol in 

 boiling nitric acicl. 



The wax thivs obtained, whevi pure, is pale yellowish 

 Vv'hite, and (unhke bees-wax) is devoid of tenacity, and is 

 extremely brittle. 



It melts at a nuich lower temperature than that of boiliraff 

 water, burns with a bright flame, and emits an odour some- 

 what resembling that of spermaceti. 



Water does not act upon it, ii-either docs cold alcohol ; 

 but this last, vi'hen' boiled, partially dissolves it, and, upon 

 cooling, deposits the greater part ; a small portion, how- 

 ever, remains in solution, and may be prcsipifated by water. 



Sulphuric ether, when heated, also disi4jlve3 it; but^. 

 upon cooling, nearly the whole is deposited. 



Lixivium of potash, when boiled with the wax, forms s 

 milky solution ; but the chief part of the wax floats on the 

 surface, in the state of white flocculi, aud appears to be 

 converted into a soap of difficurt solubiHty ; it is no longer 

 inflaiTimable, and, with water, forms a turbid solution, 

 from which, as v\ell as from the solution in potash, the 

 wax may be precipitated by acids. 



Annnonia, when heated, also rlissolves a small portion of 

 the wax, and forms a solution very similar to the former. 



Nitric and muriatic acids do not seem to act upon the 

 wax : the iHl-cts ol' sulphuric acid have not been examined. 



When the properties of this substance are compared with 

 those of bees-wax, a difference will be perceived ; and, on 

 the contrary, the most striking analogy is evident between 

 the wax of lac and the myrtle wax which is obtained from 

 th.c Myrica ccrifvra. 



Aa 



