LIFE: ITS ORIGIN AND NATURE 21 
is a question for future research to decide. The 
fact remains, however, that life manifests 
through such a body, and that this body is the 
product of evolution and heredity on one hand, 
and of a combination of elements, on the other, 
—which elements are constantly being replaced, 
as the various tissues and organs of the body 
are repaired and replaced by the foou material 
eaten. 
The matter of which our bodies are composed 
must be the same matter, in its ultimate anal¬ 
ysis, as all other matter in the universe. It has 
been contended e. g. that life originated in the 
sea, or at least in shallow pools which had 
been left after the sea had receded to a cer¬ 
tain extent,—leaving the water more or less 
stagnant. It is a significant fact, in this con¬ 
nection, that precisely the same chemical ele¬ 
ments are contained in living human beings as 
are contained in sea-water. These elements 
are: sodium, calcium, magnesium, potassium, 
chlorine, sulphur, carbon, hydrogen, oxygen 
and iron. The composition of the air is nitro¬ 
gen, oxygen and carbon. The elements contain¬ 
ed in living matter are these identical things! 
It has been suggested that, at the time when 
life was supposed to have originated upon our 
planet, the air was more or less saturated with 
carbon, and that this element, one of those es¬ 
sential for all life,—was largely instrumental 
in rendering possible the original “creation” of 
living matter. 
A great deal of work has been done, of late 
years, in the field of organic chemistry—that 
is to say, the chemistry of living plants and an- 
