52 Notices of the Labours of Continental Chemists. 
should have taken full effect in this case, and mainly, perhaps, 
under the second quadrant, I ascribe to the age and general 
weakness of the fence. 
Additional memorials might here be adduced in evidence, 
and of similar character to the foregoing; but having already 
occupied more space than I intended, I must now leave the 
question of a general whirlwind rotation in this and other tor- 
nadoes to the candid consideration of impartial inquirers. 
New York, July 12, 1842. 
IX. Notices of the Results of the Labours of Continental Che- 
mists. By Messrs. W. Francis and 'T, G. 'TILLey*. 
[Continued from vol. xxi. p. 452.] 
On Perhydrosulphocyanic Acid. 
M VOLCKEL has made some investigations of this 
e@ 
body. He recommends the following as the best 
means of its preparation:—A cold saturated solution of the 
sulphocyanide of potassium in water is mixed with from 6 to 
8 times its volume of strong hydrochloric acid, and allowed to 
stand for 24 hours. This mixture becomes thick, and after 
some minutes assumes a yellow colour. In about an hour it 
loses its glutinosity, giving out carbonic and hydrocyanic acids, 
and becoming a mass of small acicular crystals. To obtain 
the perhydrosulphocyanic acid pure, these are to be washed 
with cold water. 
It is slightly soluble in cold water, but perfectly so in hot, 
out of which it crystallizes on cooling in yellow needles. It 
is also soluble in sether and alcohol. ‘These solutions react 
slightly acid, and give reactions with metallic salts; with 
acetate of lead, yellow; the same with nitrate of silver, in the 
latter changing easily in colour, owing to the formation of the 
sulphuret of that metal; with perchloride of mercury, yellow- 
ish white; with sulphate of copper, yellow; with chloride of 
tin, yellow; and with solution of platinum, brown-yellow. 
It does not give precipitates with the other metallic salts. 
He found the composition to be C? N? H® 8°, which results 
agree with those of Woskrensky. ‘To ascertain the atomic 
weight the lead salt was examined: it was found to be C* N? 
S* Pb. The salt was obtained by precipitating a solution of 
the acid in water, by acetate of lead. The atomic weight is 
2226'72, the equivalent of hydrogen being replaced by 1 
atom of lead. 
* My friend Mr. Croft having been called from this country by his ap- 
pointment to the Professorship of Chemistry in the University of Toronto, 
these notices will be continued in future, by Mr. Tilley and myself.— 
W. Faancis. 
