CHEMICAL SCIENCE. 



RECENT CHEMICAL DISCOVERIES. 



M. PASTEUR, of Paris, has availed himself of the beautiful discov- 

 ery of M. Biot, of the influence of chemical composition in altering- 

 the rotation of polarized light, to show that the tartrates and paratar- 

 trates differ from each other only in the form of their crystals. 



M. Ossian Henry has communicated to the Paris Academy of 

 Sciences a memoir upon the existence of two new bodies belonging to 

 the amide series, one a limpid yellowish oil, lighter than water, and 

 disengaging a strong and penetrating odor, which he considers a bi- 

 sulphuret of amidogen, the other a delicate yellow oil, which, when 

 burnt, gives out an alliaceous smell, combined with a citron-like odor, 

 which he regards as a sulphocyanuret of amidogen. 



In the Brussels Academy, M. Louyet has given the results of some 

 experiments on the passage of hydrogen gas through solid bodies, 

 by which he shows that this subtile gas passes with facility through 

 paper, and even through leaves of gold and silver. By directing a 

 stream of the gas on one side of the leaf, it may be lighted on the oth- 

 er. As proving the extreme tenuity of the gas and the porosity of 

 the metals, this is important. 



Anhydrous nitric acid, which has not hitherto been procured by 

 chemists, has at length been prepared by M. Deville, of Besancon, 

 France, by passing perfectly dry chlorine over equally dry nitrate of 

 silver ; no action takes place at ordinary temperatures, but the nitrate 

 must be heated at first to 203 Fahr., and then lowered to 140 or 150; 

 the decomposition then proceeds quite regularly. At first hyponitrous 

 acid is formed, but on lowering the temperature the new substance is 

 deposited in crystals, in the cooled part of the apparatus ; although a 

 cold of 6 was employed to condense the vapors, the crystals were 

 found to form when ice alone was used. The vapor of the anhydrous 

 nitric acid penetrates caoutchouc tubes with such ease, that it is 

 necessary that all parts of the apparatus through which it passes 

 should be solidly joined. The anhydrous nitric acid forms large, bril- 

 liant, colorless crystals in six-sided prisms of the trimetric system. 



