TRANSFORMATION OF ARSENIC INTO A SOLID HYDRIDE- 32 7 
on albumen. When milk is operated on, the casein is first 
modified, the fatty matters resist longer, and the lactine is 
not at all affected. 
Amylic alcohol acted on by ozone gives first valerol and 
then valerianic acid. 
Oil of cinnamon condenses a large proportion of ozone 
without being oxidized, but yields it up to substances more 
easily affected. In this way ozonized oil of cinnamon rapidly 
decolorises solutions of indigo. 
Purified bile is not acted on by ozone; but fresh bile is 
quickly decolorised, the action being limited to the destruc¬ 
tion of the colouring matter, and perhaps also the mucus. 
Among the organic substances most eager for ozone is 
tannic acid. The author has not studied this reaction 
deeply ; but he is certain that oxalic acid is formed, and a 
body which quickly reduces the cupro-ammoniacal liquid. 
M. Besanez, as regards ozone, confirms a fact remarked 
by M. Chevreul, viz., that the presence of an alkali singu¬ 
larly hastens the oxidation of organic matters. The author 
also quotes an observation by M. His, who remarked that 
blood is so completely burnt by ozone that the residue is 
composed of scarcely anything but mineral substances. M. 
Erdmann has observed that ozone transforms indigo into 
isatine .—Repertoire de Rharmacie. 
ON THE TRANSFORMATION OF ARSENIC INTO A SOLID 
HYDRIDE UNDER THE INFLUENCE OF NITRIC ACID. 
By Dr. Blondlot. 
It is well known that when more or less diluted acids 
disengage the hydrogen of water in the presence of zinc or 
iron, the nascent gas, if in contact with a soluble compound 
of arsenic, forms with the latter a gaseous hydride having 
the formula AsH 3 . But to this general fact there is one 
exception, which I believe to be unique, and to which I 
desire to call attention, inasmuch as it may have great im¬ 
portance in toxicological researches. Nitric acid and its 
derivatives, under the conditions mentioned, only produce a 
solid hydride, having the formula As 2 H, which is precipi¬ 
tated upon the zinc in the form of brown flocculi. 
This characteristic reaction is evidently due to the forma¬ 
tion of a certain quantity of ammonia, and is produced even 
