706 TRANSACTIONS OF SECTION K. 
conceived opinions than with the methods of exact science, that simply asks and 
inquires, unconcerned for the answer. 
In the period preceding ours the dogma prevailed that the phenomena of 
life ought to be interpreted merely mechanically. A plant and an animal ought 
to be mechanisms, machines, nothing else, but of so complicated a construction 
that analysis is even yet unable to explain this merely mechanical machinery. 
In still older times people believed a vis vitalis to be active in the organism 
that did not accord with any other power in nature and that caused life. But 
this vis vitalis came more and more into contradiction with the principles of 
science until at last the contrary doctrine arose, that life was only a complicated 
example of the processes predominant in lifeless nature. This opinion was 
fcunded on the knowledge that plants and animals are composed of chemical 
combinations known also outside the organisms; that these combinations 
influence one another according to the universal chemical laws; that everywhere 
in the living body physical powers are active. In this manner physiology 
becomes the chemistry and physics of organisms. 
But the greater the progress in experimental physiology, the better we learn 
to use our knowledge of non-living matter for the explanation of the processes 
of life, the more we understand that a complete physico-chemical analysis is 
impossible for any important process of life. Behind all the physico-chemical 
facts found out by our physiological studies an unknown factor is hiding, an x 
not to be solved by levers and screws and chemical reagents. For my part I 
refuse both the exclusive vital and the exclusive mechanical dogma, but I do 
not wish to subordinate the living to the lifeless matter and to draw from 
the dominion of lifeless nature only parallels for the explanation of life. 
I am sure that the laws of energy are valid in the organism as well as in 
unorganised nature, and that the change of matter and of power in animals and 
plants depends only on them. Life is based upon such transformations of 
energy—I call them ‘ Elementarprozesse’—and these elementary processes are 
bound to elementary mechanisms in the cells of animals and plants. These 
elementary processes and elementary mechanisms are not thrown together with- 
out order in the living body: they are united by an invisible string or chain 
and this invisible chain or force that maintains the order among the elementary 
processes represents the true difference between life and any event in lifeless 
nature. I call it the ‘ Lebensprinzip.’ The single elementary processes are 
accessible to physiological analysis; not so the ‘ Lebensprinzip.’ Therefore the 
elementary processes form only one part of the living creature: the ‘ Lebens- 
prinzip’ forms the other part. By the latter the former are united to a living 
unity, an individual; and it can continue the individual in its offspring. In the 
ontogeny each stage of development from the egg-cell to the adult state is 
united by the ‘ Lebensprinzip.’ 
Each elementary process in animals and plants can be imagined by itself; not 
so the ‘Lebensprinzip.’ It shows only the relations among the elementary pro- 
cesses or mechanisms, therefore it is a law, that like all laws is invisible and 
impalpable. The ‘Lebensprinzip’ is the ordered connection of the elementary 
mechanisms within the living body; its ordered efficacy excludes an accidental 
aggregation of the elementary mechanisms in the body of plants and animals. 
Therefore life has its own laws as well as light, heat, chemistry : which does 
not exclude the fact that the physico-chemical laws reign in the elementary pro- 
cesses of a living body. Thus any mystical interpretation of the ‘ Lebens- 
prinzip’ is excluded, as it was applicable to the old vis vitalis. The ‘Lebens- 
prinzip’ is no force or power: it is a principle of succession, of order, of 
regulation, of harmony. ‘ 
2. Ammonium Humate as a Source of Nitrogen for Plants. 
By Professor W. B. Borromury, M.A. 
In a communication to this Section last year attention was called to the 
effect of soluble humates on plant growth. Further investigations show that 
ammonium humate can supply the nitrogen need of plants if soluble phosphates 
and potassium salts are present in the culture solution. 
Pure ammonium humate was obtained by extracting bacteria-treated peat 
with distilled water, precipitating humic acid from this extract by hydro- 
