108 Scientifie Intelligence. 
_ An interesting fact bearing on this, is the manner in which the mix- 
ture of hypo-nitric acid decomposes ferro-cyanide of potassium. If we 
mix in a tube closed at one end,a solution of the ferro-cyanide with an 
acid solution prepared-as above described, and then invert the tube in 
water, a violent disengagement of gas takes place, which is found to be 
pure nitric oxide, ats ‘the solution contains. nitrate of potassa and the 
ferricyanide, 
This Scedeeeiaaath cannot be atiribated: to the nitric. ete contained 
in the mixture, for we find that pure nitric acid if slightly diluted, does 
not decompose the salt, and as neither the hypo-nitric nor nitrous — 
can exist in the presence of water. 
_ It is well known that ozone decomposes the iodide of setanslaii libs 
erating iodine. If to a solution of the iodide, we add the acid liquor 
above mentioned, an abundant escape of nitric oxide takes place, while 
iodine is precipitated and nitrate of potassa forms. Pure nitric when 
diluted with the same portion of water as in the acid mixture; does not 
decompose pure iodide of potassium. 
. The results of Fellenberg are certainly possessed of great sabetdats 
The production of nitric acid from the elements of the atmosphere by 
electricity, was long since noticed by Cavendish, and is a well estab- 
lished fact; but that this acid is formed by the action of phosphorus on 
air, is a new and highly interesting result. That this highly oxidized 
body should be generated in the presence of phosphorus, seems at first 
paradoxical ; and we can only-refer it to that mysterious force, which 
Berzelius. has named catalysis, and which is in fact only a manifesta- 
tion of the law announced by La Place, that ‘¢a molecule set in motion 
by any power, can impart its own motion to another molecule with 
which it may be in contact.” In other words, the phosphorus, while in 
the act of oxidation, communicates its own peculiar state to the nitro+ 
_gen, which is thus enabled to combine with the oxygen and generate 
nitrous acid. ‘This certainly affords us a very striking illustration of 
that law, and we think that this phenomenon is incapable of explana- 
tion’on any other principle. . M. Marignac has suggested that electricity 
generated by the oxydation of the phosphorus may be the cause. This. 
however seems improbable, as it has not been shown that it is excited 
during the process, and the theory rests on the idea that all chemical 
action is attended by a development of electricity. But when we con- 
sider that our most powerful electrical discharges can generate com- 
paratively very minute quantities of ozone, the amount of electricity 
can be supposed, under a? circumstances, to be generated by the 
ae of a omall Atione 6 vitae seems meee inadequate to 
result. 
