Intelligence and Miscellaneous Articles. 253 



accompanied with any sensible increase of temperature. The mix- 

 ture was colourless, and yielded very dense white vapours of nitric 

 acid. When heated to a temperature which never exceeded 302°, 

 and was kept as near as possible to 212°, 82 parts of nitric acid of 

 specific gravity To 20 were distilled; its density remained l - 520, and 

 its boiling point was from 185° to 188° Fahrenheit. 



A third rectification with sulphuric acid effected no change either 

 in the properties, density or colour of the nitric acid. — Journal de 

 Pharmacie, t. xxvii. p. 275. 



COMPOSITION OF SUGAR OF GELATIN. 



M. Boussingault observes, that the existence of sugar of gelatin 

 discovered by M. Braconnot had been questioned by several chemists. 

 It was obtained by him by acting on glue with sulphuric acid ; and 

 on following his directions M. Boussingault obtained the sugar 

 in question, and leucin. The composition and constitution of this 

 sugar, according to M. Boussingault, are, — 



By experiment. By calculation. 



Hydrogen 6-44 6-36 H 3G 



[ Carbon 3385 34* C 32 



Oxygen 39"71 39'59 O 14 



Azote 20" 2005 N 8 



10000 10000 



Sugar of gelatin is readily combined with oxide of silver ; the com- 

 pound forms colourless crystals, which are but slightly soluble in cold 

 water. They consist of 



Hydrogen 1*21 



Carbon 1366 



Oxygen 1231 



Azote 8-07 



Silver 63-95 99"2 



Sugar of gelatin combines also with the oxides of copper and of lead ; 

 these two compounds are very soluble in water ; the cupreous com- 

 pound is a crystalline mass of an azure blue colour ; that of oxide 

 of lead crystallizes in fine colourless needles ; its solution is totally 

 decomposable by carbonic acid. The composition of both these 

 compounds is analogous to that of the silver compound. — Journal de 

 Pharmacie, t. xxvii. p. 35. ______ 



LACTATE OF UREA IN URINE. 



MM. Cap and Henry some time since expressed it as their opinion 

 that urea existed in urine, combined with lactic acid, and probably 

 also the phosphoric ; the correctness of these opinions having been 

 questioned by M. Lecanu, the authors have again investigated the 

 subject, and they are of opinion that the following experiments de- 

 monstrate the accuracy of their statement. 



When fresh human urine is evaporated to about five-sixths of its 

 bulk, at a temperature not exceeding 248° Fahr., there is obtained, 



