764 
MR. BRODIE ON THE CONDITION OF CERTAIN ELEMENTS 
materials, as that the laws of motion should be different in different bodies. I there- 
fore considered attentively what we really knew of the laws of chemical change in 
these bodies. Examples occurred to me, both of the chemical division and che- 
mical synthesis of the elements, by which various phenomena hitherto obscure might 
be explained. The experiments of the first class prove that a division'^of the elemental 
bodies which is known to occur in certain cases of chemical change, is truly a che- 
mical and not simply a mechanical division of these substances. This is shown by 
the fact that the particles of the element thus separated show the peculiar combining 
properties of “ nascent bodies.” It is not necessary to my argument that the precise 
view which I have given of the nature of this ‘‘nascent state” should be admitted; 
provided only it be allowed, that these properties depend upon the fact that the par- 
ticle is issuing from a state of combination, which is generally allowed. 
1 . No theory of chemical change has given rise to more discussion among chemists, 
than the usual mode of the formation of sulphuric acid by the mutual action of sul- 
phurous acid, nitric oxide, air and water. On this question there are some six re- 
cognized theories. The problem is simply this : Why, when the oxygen is made a part 
of this system of particles, does it possess oxidizing properties which otherwise it has 
not? On the view I have stated the cause is plain. When nitric oxide acts chemi- 
cally upon oxygen, the gas is thrown into a polar condition; the result of which is 
to give to other particles of the mass a combining power, in a direction the reverse 
of that in which the oxygen combines with the nitric oxide; the change being in all 
respects analogous to the decomposition of water by the joint action of nitric oxide 
and chlorine* ; thus — 
-|- h — 
NO 2 00 SO^^NO.+SOg. 
) 
The best of the other explanations of this fact is, in my opinion, that of Peligot'I', who 
considers the formation of the sulphuric acid to be the result of the successive forma- 
tion and decomposition of nitric acid. This, however, does but shift the difficulty to 
another point ; for why does nitric acid oxidize sulphurous acid ? In truth, in this 
case, a perfectly similar polarization takes place within the acid itself — 
+ — — 
(N05=)N03 O O S02=N04-1-S03. 
v ) 
* In the following experiments I am compelled to call by the same name three very different things — the 
isolated element, the particles of the element at the moment of their chemical separation or synthesis, and the 
combined element ; and I wish to observe, that when I state that there is a chemical difference between the 
particles of the element, I mean simply the particles of which the element consists. The chemical nature of 
these particles is a further question. 
t Annales de Chimie, 3rd Series, vol. xii. p. 263. Peligot states that nitric oxide always forms hyponitric 
acid and no nitrous acid, in contact with atmospheric air ; but it by no means follows, even if this be the sub- 
stance formed with atmospheric air alone, that the same substance is formed in the presence of sulphurous 
acid ; indeed, on the view I have given, a difference in the reaction would rather be anticipated. 
