540 Analysis of the Cerelml Matter of Man^ [Mat, 



very near the first substance. It differs from it by its reddish 

 brown colour, by its smaller consistence, by a slight taste of 

 boiled meat which the first substance has not, and by a greater 

 tendency to crystallization. 



This difference is produced by a certain quantity of animal 

 Blatter, of which we shall speak hereafter, and which may be 

 .separated from the fatty matter by means of cold alcohoL 



SS-CT. VI. - 



Of the yelloiv aqueous liquor which remains after the separa- 

 tion of the two fatty substances^ ly cooling and by evaporating 

 the alcohoL 



When one has deprived the brain, by means of alcohol, of 

 every thing soluble in that liquid^ and separated, by the methods 

 above described, the two fatty substances from the alcohol, there 

 remains a liquor of a brownish yellow colour, which has the 

 taste of the juice meat with a little sweetness^ This liquid 

 reddens litmus ; and is precipitated by lime-water, infusion of 

 Butgalls, &c. 



To learn the nature of the substances contained in that liquid 

 we in the first place diluted it with a quantity of distilled water, 

 and then poured into it lime-water as long as any precipitate 

 continued to fall. The matter washed and dried in the open air 

 had a yellow colour. When calcined it assumed a black coIouFj 

 owing to the presence of a little animal matter, which is decom- 

 posed by the heat. 



This substance thus calcined and redissolved in nitric acid was 

 again precipitated white by ammonia. It was not blackened by 

 exposure to heat, and possessed the characters of phosphate of lime. 



After having ])recipitated, by means of lime, the phosphoric 

 acid contained in the aqueous liquid, w^e evaporated it to dryness 

 with the requisite precautions. Tlie matter which it furnished 

 weighed 4'5 grammes (69'5 grains troy). In this state it had 

 a reddish brown colour, was semitransparent, had a taste similar 

 to the juice of meat with a little sweetness; it dissolved in 

 alcohol with great facility, leaving only some atoms of a saline 

 matter which effervesced with acids. 



Exposed to the air it became soft by attracting humidity. A 

 portion of this matter being heated in a platinum crucible, 

 swelled up considerably, and emitted vapours which had the 

 odour of burning animal matter. It left a charcoal, which 

 yieidedj when washed with water and the liquid was evaporated^ 

 a L't .is pure carbonate of potash. 



It follows, evidently, from these experiments, that the 

 aqueous liquid contained uncombined phosphoric acid and 

 phosphate of potash^ or perhaps superphosphate of potash and 



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