Intelligence and Miscellaneous Articles. 297 



of caoutchouc and a large proportion of a substance possessing in 

 some respects peculiar properties, which appear to place it interme- 

 diate between caoutchouc and the resins, to the latter of which it 

 bears the greatest resemblance. Dr. Christison suspects that it is not 

 nutritive, and he observes that it differs totally from the juice of the 

 Palo di Vaca described by Humboldt as supplying the vegetable milk 

 of the province of Caraccas in South America, as well as from the 

 juice of the papaw tree ; the solid contents of the former, from a late 

 analysis by Boussingault and Mariano di Rivero, appear to be a large 

 proportion of a substance analogous to fibrin, and a little wax and 

 sugar, while from the experiments of Vauquelin the juice of the 

 papaw tree contains two principles analogous to albumen and casein. 

 — Ibid. 



PRECIPITATE OF CHLORIDE OF IODINE BY SULPHURIC ACID. 



Chloride of iodine (chloriodic acid) is, as is well known, very so- 

 luble in water ; but it was not till lately observed that it is readily 

 precipitated from solution by sulphuric acid : this occurs when a great 

 excess of the acid is poured into the solution, and the chloride of 

 iodine precipitates unchanged. M. Serullas, who made this experi- 

 ment, also mixed muriatic and iodic acids in proper proportions; and 

 he observed, that on pouring sulphuric acid into the watery solution of 

 this mixture, the iodine and chlorine precipitated in the state of chlo- 

 ride of iodine, whilst the other elements of the acids combined to form 

 water. 



It may perhaps be thought, from this experiment, that the solution 

 of chloride of iodine in water is a simple mixture of muriatic and 

 iodic acid ; but this opinion is inadmissible, because it is well known 

 that by means of aether all the chloride of iodine may be separated 

 from water,— Journal de Pharmacie, April 1830. 



BUTYRIC ACID IN URINE. EXISTENCE OF LACTIC ACID. 

 M. Berzelius has informed M. Chevreul, that by treating urine 

 with sulphuric acid he has succeeded in separating butyric acid from 

 it : he has also stated that lactic acid, which some chemists were in- 

 clined to consider as acetic acid combined with a peculiar matter, is 

 really a peculiar acid. One of the experiments on which this opinion 

 is founded, is, that when ammonia is combined with lactic acid, and 

 the product is distilled, no acetate of ammonia is obtained, which 

 ought to happen if lactic acid were a combination of acetic acid. — 

 Ibid. — 



FUMING NITRIC ACID. 



In his laboratory, at the temperature of 14° Fahr., M. Mitscherlich 

 heated several pounds of fuming nitric acid, slowly, in a retort, the 

 neck of which and the receiver were cooled by a mixture of muriate 

 of lime and snow ; no gas was evolved, but the acid condensed in 

 the receiver consisted of two layers, the separation of which took 

 place after every mixture by agitation. The lighter fluid boiled at 

 82 0, 4 Fahr. retaining that temperature until the last portion had eva- 

 porated ; its specific gravity was 1*445 ; it decomposed when mixed 



N. S. Vol. 8. No. 46. Oct. 1830. ' 2 Q with 



