136 Metnoir on the Kalure of fat Sulilances. 



into this licjuor, still hot, some muriatic acid, which occasioned a 

 considerable extrication of sulphuretted hydrogen gas, and there 

 was precipitated a fatty mass of a brown colour, and having the 

 smell of burnt wool: it resembled pitch; when melted in water 

 to wash it, it allowed itself to be drawn into threads like tur- 

 pentine. When cold it is dry, brittle and pulverulent, like a re- 

 sin ; it contains a notable quantity of sulphur^ as I ascertained 

 by fusing it on a silver plate, which became a deep black. Cold 

 alcohol has no action on this substance ; but when it is boiling 

 it dissolves it nearly like wax, and upon cooling a yellowish flaky 

 precipitate is formed ; the liquor separated from this precipitate 

 becomes milky l)y an addition of water, and contracts a smell 

 and taste very strongly of spirit of cochlearia, owing to the pre- 

 sence of the sulphur. 



Boiling oil of turpentine, as well as the fixed oils, exhibited 

 no disposition to dissolve this substance, and in this respect it 

 seems to be removed from fat bodies. 



It is dissolved very easily in cold potash, and the acids may 

 again precipitate it : it differs therefore from the oil which Pa- 

 pin's digester can extract from hair, which is very insoluble in 

 the alkalies. When distilled it gave a brown grease, some sul- 

 phuretted hydrogen gas, and a liquid which renders the blue 

 vegetable colours green : but no carbonate of ammonia is sub- 

 limed. This substance therefore contains azote, but much less 

 than v.'ool. From the ten grammes of wool dissob.ed in potash, 

 I could precipitate by the acids only one gramme and two 

 decigrammes of fatty sulphuro-azotic matter : hence the soapy 

 liquor ought to contain some other parts of the wool soluble in 

 water. In fact, by evaporation we obtained a yellowish residue 

 in considerable quantity, composed of muriate of potash and a 

 substance forming tlie greater part of the soap of wool. As al- 

 cohol easily dissolves it, it was easy to separate it from the mu- 

 riate of potash. Thus isolated it was of a shining yellow colour, 

 perfectly transparent like a gum, but of a peculiar odour, which 

 I cannot better com])are than to that of the grain of trigoiiella, 

 Fceniim grcecum ; its taste has nothing remarkable. This sub- 

 stance is dissolved in ether, but better in alcohol; and particularly 

 in water. The infusion of gall-nuts precipitates it entirely from 

 its aqueous solution, under the form of a flaky white sediment 

 soluble in alcohol. 



The aqueous solution of the same substance is not disturbed 

 either t)y the nitrate of barytes or the sulphate of iron : only the 

 latter raises the colour ; but tlie acetate of lead forms in it a 

 flaky white precipitate entirely soluble in nitric acid. 



When burned on a capsule of silver, it swells up, giving out 



the 



