Page:Proceedings of the Royal Society of London Vol 4.djvu/173

Rh to the quantity of nitrogen it contains. This law is found to ex- tend to those parts of plants which are not in solution in water, but which remain in their natural state of elaboration, only having their texture broken down.

The author is led to infer from his experiments that the chemical action to which any vegetable matter is naturally disposed, may, to a certain extent, be changed into some other, differing both in its kind and in its products ; and that in order to effect such a change nothing more is required than to excite in other vegetable matter mixed with the former, some action which shall preponderate over the rest, so that the whole mass may obey this new and predomi- nant influence. The vapour which is disengaged during the rapid decomposition of vegetable matter he finds to be highly noxious ; and thence draws the inference that the Author of the universe has wisely ordained, that, when young plants, containing large quantities of nitrogen, are by any means checked in their growth, they shall be consumed by certain insects ; which insects may be conceived to form one of the links of that harmonious chain which binds together all the parts of the universe.

The relation between the decomposition of vegetable matter and the growth of plants is apparent from the similarity of the influence of nitrogen on both these processes : this double function which nitrogen performs in favouring chemical decomposition by the roots of plants at the same time that it assimilates the matter thus formed in their other parts, is regarded by the author as another link in the same chain. In support of this view, he adduces the difi'erent che- mical constitutions of the roots of the same plants when very young, and when fully grown. He finds that when plants have to perform the important offices of providing nourishment for the rapid growth of their young and tender shoots, they contain a quantity of nitro- gen two or three times greater than that which they possess when fully grown ; and he concludes by showing that, in accordance with these views, the seeds, roots and plants when placed in highly de- composing or decomposed matter, cease to grow, and under these circumstances, their germinating or vegetating power being super- seded by the chemical action established in the matter which sur- rounds them, the whole becomes one mass of contaminated and in- fectious matter.

George Barker, Esq., was balloted for, and duly elected into the Society.

A paper was read, entitled, "Experiments on the chemical consti- tution of several bodies which undergo the vinous fermentation, and on certain results of the chemical action." By Robert Rigg, Esq., F.R.S.