260 Translations and abstracts from the French. 
It is evident from the preceding statement, that chlorine 
combined with cyanogen, exerts an action upon water anal- 
ogous to that of other chlorides, iodides and bromides ; that 
this combination is transformed, by the decomposition of 
water into hydro-chloric. and cyanic acid; that the latter 
being more fixed and very stable, may be separated, by 
evaporation, from the ike which is very volatile. 
The discovery of the perchloride of cyanogen, indepen- 
dently of the interest which it presents in itself, becomes 
more important by the discovery of cyanic acid, which re- 
sults from it, pace whe latter creates a class of salts before 
unknown to chemistry. 
. Serulas nar combined the acid with several oxides, but 
as the Seanaies may be numerous, he reserves them for the 
subject of another memoir.—Annales de Chimie et - Phys- 
igue, Aout, 1828. 
sulphate of zinc, and obtained a colorless anid, which pre- 
served its qualities three years and a half: u dro ops were 
sufficient to kill a large dog.—Ann. de Chime. A ee Phys. 
2. Specific gravity considered as a mineralogical charac: 
ter.—The statement given in treatises of mineralogy, of the 
specific ae of different ‘varicties of the same substance, 
shews so much discordance among these varieties, as to pre- 
vent specifi vba Bowl from being worthy of any reliance as a 
character. ads dant, apeDeCN that this difference 
has liye from the presence of foreign substances in 
them, has Ces pains to ascertain what atigal agreement 
there is, in the specific SE of the same substance in @ 
pure state in its differen 
The specific gravity of carbonate of lime, varies accord- 
ing to the books, from 2.324 to 3.672. M. Beudant, in limit- 
ing himself strictly to those istietiss which were identical in 
chemical composition, so as to avoid the influence of mix- 
tures, finds indeed in different varios some difference of 
specific gravity, but far more limited in its extent than ap- 
