new Substances y ly the Action of Sulphuric Acid. 135 



bases. With lime it produces a permanent salt crystallised in 

 rounded groups. With magnesia the salt formed appears as 

 small granular crystals, which do not deliquesce in the air, in 

 which respect it differs from the nitro-saccharate of magnesia. 



Examination of the alcoholic Liquid from which the Leucine 

 had precipitated. 



The solution still retained a quantity of leucine. On evapo- 

 ration it left a thick granulated residue, out of which cold alcohol 

 dissolved a reddish extractive matter, leaving the leucine un- 

 touched. This extract is slightly deliquescent, and has rather a 

 bitterish taste of burnt roast meat. It was not changed by sul- 

 phuric acid ; its solution in water was hardly troubled by sub- 

 acetite of lead and infusion of galls, and not altered by sulphate 

 of iron. 



Of the Substance insolulle in Alcohol. 



The extractive matter resulting from the muscular fibre treated 

 with sulphuric add was only partially soluble in alcohol, as before 

 described; the portion insoluble in this re-agent was the most 

 abundant. 1 dissolved it a second time in water, to separate the 

 sulphate of lime with which it was mixed, and obtained by eva- 

 poration a yellowish-brown extractive matter, slightly deliques- 

 cent, and having a taste of broth, probably owing to the leucine 

 which it still retained. In the fire it swelled and burnt like mat- 

 ter moderately animalised, and left a coal easy to incinerate. 

 The solution of this extract in water gave a reddish precipitate 

 with infusion of galls, which was loose and flocculent, like that 

 which arises from matter little animalised. Persulphate of iron 

 gave a copious reddish flocculent precipitate; nitrate of silver, a 

 grey precipitate; nitrate of mercury, a white coagulum. As the 

 sub-acetite of lead gives also a copious white precipitate with this 

 extract, and does not disturb the solution of leucine, I hoped 

 to be able by this means to separate the two ; and in consetpience 

 added this re-agent, and obtained the white precipitate, and 

 from the filtered liquor I first separated the lead which it retained 

 by carbonate of ammonia, and evaporated the syrupy residue; 

 but I procured very little leucine by this process. 



Action of Sulphuric .-^cid on Wool. 

 Fifteen grammes of white woollen cloth, cut into small shreds, 

 were moistened with sixty grammes of sulphuric acid, lowered 

 with a quarter of its weight of water. A little sulphurous acid 

 gas was given out, and the wool became reddish, but without 

 perceptibly softening; the mixture was then exposed to a water- 

 boiling heat, on a sand bath, and with shaking it was changed 

 to an uniform mucilage. The digestion was continued till a 



complete 



