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A. H. Church. 
idea of the infinite possibility of elaboration in the relations of all 
the ions of living cytoplasm and their molecular reserves. 
To the biologists of a preceding generation, brought up on 
animal physiology as presented in the human body, the distinction 
of “ living ” as opposed to “ non-living” organization was based on 
the conception of Katabolism, as involving a “combustion-process,” 
or internal liberation of energy for vital operations; and so far the 
flame is the legitimate image of biological life. Tbe work of Pasteur 
on Saccharomyees, of Sachs on photosynthesis, and later of 
Winogradski on Nitro-bacteria, showed that other external sources 
of energy are available to organism ; and, since the idea of breaking 
down demands a preceding effort of building up, the primary defini¬ 
tion of life was extended to anabolism; the synthetic processes of 
organism being clearly more essential than the destructive operations 
associated with the performance of animal work. 
From a botanical standpoint, autotrophic organism working in 
terms of an external source of solar energy must be regarded as 
the primary case ; and the recognition of the initiation of “ Life ” 
thus extends still further back in the problem of more and more 
elementary syntheses of protoplasm ; as for example to proteid- 
complexes of more elementary nature, as considered in the synthesis 
of polypeptides, and even to the non-nitrogenous synthesis of 
presumably carbohydrate material. So that while animal physiolo¬ 
gists may discuss the more fundamental efforts of “ life,” as expressed 
in the elaborations of proteid from sugar and ammonia, the antecedent 
synthesis of sugar involves the apparent adoption of formaldehyde 
as “ non-nitrogenous protoplasm ” (Cross and Bevan, 1912). But 
it is evident that all such syntheses are the necessary preliminary 
stages of a continued sequence of anabolic processes; and 
it is not possible to say that “ life ” began at any one stage 
more than at any other. Further complications only continue the 
same story, and “reversible enzyme-actions” are possibly but 
of the same class of phenomena as reversible ionic reactions 
involving interchange of OH' and H’ ions. Taking the actual 
starting point as the introduction of an external source of energy, 
beyond that provided by the inorganic material of a world-conden¬ 
sation, this may be traced in the action of solar radiation, a factor 
of the solar-system, again older than the earth itself. The point 
at which it is applied, so far as is known, is to be sought in the 
chemical reactions antecedent to the production of a monosaccharide 
sugar, initiated by the dissociation of the ions of C0 2 in sea-water, 
and the building of open chains of CHOH groups. In so far as this 
