the expanding living substance will give rise to a restitution of the entire mass more in the likeness of the higher protoplasm disintegrated by the more subtile dynamical influences. Thus the constitution of the protoplasm at the very beginning of its next pulse of recomposition will, by this slight increment of complication, resemble a whit more its molecular state, when at the height of its former expanding pulse. The decomposition caused by the combined specific energies of the medium will be followed by a somewhat higher composition.
The elaboration of organic substances in plants is at all times notably effected by a process similar to the one here indicated. It is brought about by a twofold chemical activity, incited by a specific dynamical influence of the medium. First there occurs a specific decomposition, and then, in consequence, a somewhat altered recomposition; or, technically expressed, there occurs reduction followed by substitution. It is believed that under the influence of light there is split off from carbonic acid one atom of oxygen, which is then replaced by one atom of hydrogen:2COO H2O-C2H2O2 OOO.
But, before examining the conditions under which this fundamental and most weighty transformation of the inorganic into the organic takes place, I will state, in further support of the gradual development of the living substance, that the phenomenon of individual growth gives in itself plain evidence of organic development having actually occurred in the past. Growth is essentially a concise recapitulation of developmental changes.
But, not to complicate matters too much, I have here purposely left out of consideration all manifestations appertaining to growth, as well as those appertaining to propagation. Both these phases of organic existence do not belong to the domain of production, but entirely to that of reproduction. Propagation multiplies, growth reconstructs, organic results previously achieved.
Though it cannot be denied that the attentive observation of moneric protoplasm has restricted the physical phase of the problem of life to the limits of a purely chemical question, and though it may be conceded that organic development is truly effected by means of chemical activity dynamically incited, yet with many there will persist an ungratified curiosity concerning the origin of life. This dissatisfaction, expressed in clear words, can only amount to the following objection: "Granting that motility is merely the scientifically intelligible property of a specific chemical compound, yet it has not been shown how on our planet the first organic compound has actually started into existence."
Against this rather radical claim on the science of life might be urged, that we do not precisely know how, for instance, carbonic acid has naturally originated. But we will be told that one has only to bring carbon, under certain known conditions, together with oxygen, and that then carbonic acid will invariably result.
To this might again be replied that organic substances can also be