Whatever our opinion as to its signification, osmotic growth demands the attention of every mind devoted to the study of nature. It is a marvellous spectacle to see a formless fragment of calcium salt grow into a shell, a madrepore, or a fungus, and this as the result of a simple physical force. Why should the study of osmotic growth attract less attention than the formation of crystals, on which so much time and labour has been bestowed in the past?
CHAPTER XII
THE PHENOMENA OF LIFE AND OSMOTIC PRODUCTIONS—A STUDY IN PHYSIOGENESIS
It is impossible to define life, not only because it is complex, but because it varies in different living beings. The phenomena which constitute the life of a man are far other than those which make up the life of a polyp or a plant; and in the more simple forms life is so greatly reduced that it is often a matter of difficulty to decide whether a given form belongs to the animal, vegetable, or mineral kingdom. Considering the impossibility of defining the exact line of demarcation between animate and inanimate matter, it is astonishing to find so much stress laid on the supposed fundamental difference between vital and non-vital phenomena. There is in fact no sharp division, no precise limit where inanimate nature ends and life begins; the transition is gradual and insensible, for just as a living organism is made of the same substances as the mineral world, so life is a composite of the same physical and chemical phenomena that we find in the rest of nature. All the supposed attributes of life are found also outside living organisms. Life is constituted by the association of physico-chemical phenomena, their harmonious grouping and succession. Harmony is a condition of life.
We are quite unable to separate living beings from the other productions of nature by their composition, since they are formed of the same mineral elements. All the aliments of plants—water, carbon, nitrogen, phosphorus, sulphur—before their absorption and assimilation belonged to the mineral kingdom. The carbon and the water are transformed into
sugar and fat, the nitrogen and the sulphur into albumen, and the compounds so formed are then said to belong to the organic world. These organic bodies are returned once again to the mineral world by the action of animals and microbes, which transform the carbon into carbonates, and the nitrogen, sulphur, and phosphorus into nitrates, sulphates, and phosphates. Hence life is but a phase in the animation of mineral matter; all matter may be said to have within itself the essence of life, potential in the mineral, actual in the animal and the vegetable. The flux and reflux of matter is alternate and incessant, from the mineral world to the living, and back again from the living to the mineral world.