416 NOTICES OF THE MEETINGS [March 31, 
than of a process of fermentation in which alcohol was developed 
and subsequently oxidised. An exception was also referred to in 
the animal kingdom in which fat is supposed to be formed by the 
deoxidation of sugar; but attention was drawn to the fact that this 
process admitted of another explanation, not opposed to the phy- 
siologico-chemical distinction pointed out. 
These processes were further shewn to be connected with the 
relations existing between the animal and vegetable kingdoms. The 
plant was produced from mineral compounds—carbonic acid, water, 
and ammonia,—the substances out of which the animal was formed ; 
and no instance was known of the animal appropriating and forming 
organic substances out of these compounds. This was the distin- 
guishing feature of the life of the plant, and the liberation of oxygen 
gas its most constant result. The appropriation of substances thus 
formed, and the uniting them once more to oxygen gas, was the dis- 
tinguishing feature of animal life, and the formation of carbonic acid 
gas its most constant result. Minor changes occurred; but these 
were the grand distinguishing features of the two kingdoms, the 
recognition of which by structure, function, or results could alone 
enable us to distinguish between plants and animals. 
[E. LJ 
WEEKLY EVENING MEETING, 
Friday, March 31. 
Cou. Puitie J. Yorxs, F.R.S. President of the Chemical Society, 
in the Chair. 
Joun Haut Guapstong, Esq., Ph. D., F.R.S. 
On Chemical Affinity among Substances in Solution. 
An historical sketch of the development of the ideas of chemists 
concerning ‘‘ Affinity”’ was first given. The dogma of Hippocrates 
that ‘‘ Like combines only with like,” was shewn to be superseded 
by the view of Glauber and others, that unlike substances com- 
bine most readily: and that where two bodies have an affinity for 
one another, it is a sign that they have zo affinity with one another. 
The views of Newton and Boyle in reference to the different de- 
grees of strength of affinity were then considered, and particular 
attention was directed to the doctrine of Bergmann, that when a 
decomposition takes place by means of the greater elective attrac- 
tion of a third body, that decomposition is complete. In op- 
position to this, Berthollet contended that in all such cases of 
composition, or decomposition, there takes place a partition of the 
