492 Miscellaneous Intelligence. 



resembling that of acetic acid, exactly as in the distillation of the 

 cyanate of mercury, or uric acid, or urate of mercury^ 



If urea is formed by the union of cyanic acid and ammonia, then 

 the composition of the former ought to agree with that of the latter, 

 as M. Wohler had formerly given it, supposing the cyanate to 

 contain one atom of water, as all the hyd rated ammoniacal salts 

 do. The cyanate of ammonia is composed of 56.92 cyanic acid, 

 28.14 ammonia and 14.74 of water ; so that the ultimate com- 

 position of this salt and of urea, as analysed by Dr. Prout, are as 

 follows : 



99.80 99.945 



When cyanic acid is decomposed by oxide of copper and heat, 

 it yields 2 volumes of carbonic acid gas, and 1 volume of azote: 

 when the cyanate of ammonia is decomposed in the same way, 

 equal volumes of these gases are obtained ; the same ratio of equal 

 volumes was obtained by Prout from urea when decomposed in 

 the same manner. — Annales de Chimie, xxxvii. 330. 



30. Identity of Asparagine with Ageodoite. — Ageodoite is a crys- 

 talline substance, remarked by M. Robiquet as accompanying the 

 saccharine principle in the liquorice root, and supposed to be of a 

 peculiar nature. According to M. Plesson it is identical with 

 asparagine. In does not exist in the dry root, but both the dry 

 and the fresh root contain a magnesian salt of which the acid 

 appears to be new and peculiar. — Annales de Chimie, xxxvii. 81. 



Natural History. 



1. Dependence of Sight upon the Optic Nerves. — From certain ob- 

 servations made at the Hotel Dieu, at Paris, M. Majendie is 

 inclined to doubt the absolute necessity of the optic nerves to 

 vision. A case there occurred in which the optic nerves were 

 gradually destroyed by a tumor, and yet the man saw objects dis- 

 tinctly a short time before his death. It is admitted, that the 

 sudden division of the optic nerves causes total blindness ; but it is 

 stated, that the fifth pair of nerves has an influence over the 

 senses of seeing and hearing, and it is thought possible, that when 

 the optic nerve is gradually destroyed, this pair may, in certain 

 circumstances, supply its place. — Jour, de Physiologic, viii. 27. 



2. Innocuous Nature of Putrid Exhalations, — A committee have 

 been engaged in France in examining the circumstances relative 

 to the knacker's operations. His business consists in killing old 

 worn-out horses^ and turning every part of their body to account. 



