ON PLASTERS AND SOAPS. Q33 



The filtered liquor still retained a strong saccharine taste. The filtered U* 

 It was evaporated to the consistence of a sirup, and the ace- Evaporate4. 

 tate of lead then no longer indicated the presence of suU 

 phurctted hidroL^en. My attempts to ferment it vvefe as Would not fejir 

 unsuccessful, as before the oxide of lead was separated. *^^'^"'- 

 Exposed to tb.e air, it strontjly attracted moisture: thrown on Attracted 

 burning coals^it flamed like an od: on boilingit with the red, burned >vith 

 j^ellow, and white oxides of lead, it dissolved only the yeU ftame: dissoly^ 

 low: on distilling it repeatedly with nitiic acid, oxalic acid of^ad-*formed 

 was formed: distilled in a retort on an open fire, part of it oxaiic acid. 

 rose, as Scheele observed; and by increasing the heat the its products. 

 products were an empyreumatic oil, acetic acid, carbonic 

 acid, carburetted hidrogen gas, and a light, spongy coal, 

 containing ho oxide of lead. 



Froiu what I have mentioned it might be presumed, that 

 the oil, when it had combined with the white oxide of lea^d, 

 was not in the same state as before the combination. , 



To free it from this oxide I employed acetic acid, because rated^from^the 

 the solubihty of acetate of lead would affo-d ready means oxide. 

 of separating it from the oil, the properties of which I wishe4 

 to examine. 



This oil has the cons:stence of soft fat, and the taste of ^^^ characters, 

 this animal substance when rancid. It is insoluble in water, 

 but soluble in alcohol ; from which it is precipitatfivd by water 

 as volatile oils are, and like them partly rises in dijitiilation*. 



The slightest boiling is sufficient to combine it perfectly Readily unites 

 with white oxide of lead, and give it the consistence of a )'^^^^ y,'"^'^^ <^^- 

 fttrong plaster, which does not take place with litharge, or 

 with massicot. 



The yellow and white oxides of lead cannot comlane with Neither white 



common oils. I satisfied myself of this fact by boiimp-them ."°/y-'^^w °^- 



-^ -' "> '^ ide unites witt^ 



t<)g€ther much longer, than would have been necessa'-y if I common oil. 



had used litharge. 



From these experiments it follows, that, when fat oils are Oxigen of li- 



treated with litharge, the oxigen of the latter takes from ^^^^'S^ takes 



them carbon, and previously hidrogen, to form with them dro^^en from 



water aud carbonic acid. oils, 



♦ All fat oils are soluble in alcohol j but they are far from possesiJiig ^ 



this property in so striking a manner, as after they have been boiled with 

 litharge. 



' That 



