2 
GRAND DISCOVERIES OF LIFE 
episodes than those which take place in the millions of years that 
lie between. 
Earth students sometimes marvel that when life on our globe 
is commonly conceived to start, at the beginning of Cambric time, 
it appears to spring forth in great profusion, already nine-tenths 
differentiated, that in Devonic times vertebrate animals so sud¬ 
denly rush upon the stage as to seem to be special creations, and 
that, in our own day, actual control of individual life span is in 
sight. 
It is not by paleontological contemplation that these mysteries 
are unravelled. From the strictly geological angle little hope is 
held out for a solution of these novel problems. To the zoologist 
alone the phenomena do not give up the secret of their being. 
Only concerted action on the part of all three offers clue. At first 
purely speculative working hypothesis soon assumes plausibility, 
and then through accumulation of supporting facts the plan takes 
on semblance of established theory. Finally realism supplants the 
post of fiction. 
Most momentous events connected with life’s career are those 
three great crises in biotic development, the discovery of the bot¬ 
tom of the sea, the introduction of the back-bone, and the domestic 
use of fire and all that it means in turning awry the set course of 
nature. 
Although little regarded among men amongst whom it was 
written the exposition of life’s discovery of the bottom of the sea 
seems one of the master thoughts in American philosophy. Penned 
by modest zoologist upon apparently a strictly biological theme, 
but unfortunately published in a geological journal for the special 
benefit of paleontologists, it entirely missed its high mission. Not 
only was it utterly lost on the fossil brethren, but being published 
in an out of the way channel it completely failed to gain the atten¬ 
tion of biologists among whom it should have found lodgement. 
This remarkable essay had birth under very unusual circum¬ 
stances. Possibility of the existence of a thick pre-Cambric 
succession of sediments was occupying the center of the geological 
stage both in this country and the world. Under the title of 
Algonkian the Federal Geological Survey had proclaimed with 
great eclat the recognition, beneath the known Cambric section, of 
an entirely new system of sedimentary rocks which, it was hoped, 
would prove to be comparable to Murchison’s and Sedgwick’s 
