304 Notice of some Recent 



taric or racemic acids at the temperature of 392° F., and 

 rectifying in the water hath, the product of the distillation, 

 which is a yellow matter. In this second process, the first 

 half which contains acetic acid is laid aside. The last half 

 is a yellow liquid with a feeble smell, a thick consistence 

 and an acid taste, specific gravity 1*25. It does not cry- 

 stallize at 41°. It consists of carbon 46-042; hydrogen 

 3-762; oxygen 50-195. 



It appears, therefore, to be tartaric acid, combined with 

 the half of its radicle, or pyro-tartaric acid, combined with 

 an atom of carbonic acid. Its atomic weight is 9-961, and 

 its capacity of saturation 10-04. Its salts do not crystallize 

 but present an appearance like gum. — (Journ. de Pharm. 

 May, 1835.) 



When citric acid is distilled at a temperature of between 

 392° and 482°, an acid is obtained distinct from pyro-citric 

 acid. It differs only from citric acid in having an atom 

 less water, and the same capacity of saturation. 



Nitro-sulphuric acid. — M. Pelouze formed this acid by 

 causing the deutoxide of azote to act upon a solution of 

 sulphite of potash and potash dissolved in water ; the quan- 

 tity of gas absorbed is in the proportion of 2 vols, to 1 of 

 sulphurous acid contained in the salt. Now, 2 vols, sul- 

 phurous acid, and 4 vols, deutoxide of azote, combine with 

 the alkali and form a new compound, the formula for 

 which is, Az°- SO 4 + KO. 



This salt crystallizes in beautiful quadrangular prisms, 

 but is decomposed in contact with water at the tempera- 

 ture of 32°, giving origin to sulphate of potash and pro- 

 toxide of azote. All the acids, even the most weak, produce 

 a disengagement of protoxide of azote, but when the heat 

 is gentle, sulphate of potash is formed, and deutoxide of 

 azote disengaged. Nitro-sulphate of ammonia in decom- 

 posing, sometimes gives out so much heat as to produce 

 explosions, by decomposing the sulphate of ammonia formed. 

 This salt is decomposed by the bodies which have the 

 same effect on deutoxide of hydrogen ; this phenomenon 

 takes place even with bodies which do not decompose the 

 latter. It affords a ready method of disengaging protoxide 

 of azote in the stomach. Majendie is trying its effect as a 

 remedial agent. — (Journ. de Chim. Medic, i. 438.) 



