522 
isters of the earth’s history, not only is 
there no evidence of colossal floods, tides 
and denudation, but there is incontrover- 
tible proof of continuous orderly deposition, 
such as may be witnessed to-day in any 
quarter of the globe. The same tale, with 
endless additional details, is told all through 
the stratified formations down to those 
which are in the course of accumulation at 
the present day. 
Not less important than the stratigraph- 
ical is the paleontological evidence in favor 
of the general quietude of the geological 
processes in the past. The conclusions 
drawn from the nature and arrangement of 
the sediments are corroborated and much 
extended by the structure and manner of 
entombment of the enclosed organic re- 
inains. From the time of the very earliest 
fossiliferous formations there is nothing to 
show that either plants or animals have had 
to contend with physical conditions of en- 
vironment different, on the whole, from 
those in which their successors now live. 
The oldest trees, so far as regards their 
outer form and internal structure, betoken 
an atmosphere neither more tempestuous 
nor obviously more impure than that of to- 
day. The earliest corals, sponges, crusta- 
ceans, mollusks, and arachnids were not 
more stoutly constructed than those of later 
times, and are found grouped together 
among the rocks as they lived and died, 
with no apparent indication that any vio- 
lent commotion of the elements tried their 
strength when living or swept away their 
remains when dead. 
But, undoubtedly, most impressive of all 
the paleontological data is the testimony 
borne by the grand succession of organic re- 
mains among the stratified rocks as to the 
vast duration of time required for their evo- 
lution. Professor Poulton has treated this 
branch of the subject with great fullness and 
ability. We do not know the present aver- 
age rates of organic variation, but all the 
SCIENCE. 
[N.S. Vou. X. No. 250. 
available evidence goes to indicate their 
extreme slowness. They may conceivably 
have been more rapid in the past, or they 
may have been liable to fluctuations accord- 
ing to vicissitudes of environment.* But 
those who assert that the rate of biological 
evolution ever differed materially from what 
it may now be inferred to be, ought surely 
to bring forward something more than mere 
assertion in their support. In the mean- 
time, the most philosophical course is un- 
doubtedly followed by those biologists who 
in this matter rest their belief on their own 
experience among recent and fossil organ- 
isms. 
So cogent do these geological and paleon- 
tological arguments appear, to those at 
at least who have taken the trouble to 
master them, that they are worthy of being 
employed, not in defence merely, but in 
attack. It seems to me that they may be 
used with effect in assailing the stronghold 
of speculation and assumption in which our 
physical friends have ensconced themselves 
and from which, with their feet, as they 
believe, planted well within the interior of 
the globe and their heads in the heart of 
the sun, they view with complete uncon- 
cern the efforts made by those who en- 
deavor to gather the truth from the surface 
and crust of the earth. That portion of the 
records of terrestrial history which lies open 
to our investigation has been diligently 
studied in all parts of the world. <A vast 
body of facts has been gathered together 
from this extended and combined research. 
The chronicle registered in the earth’s 
crust, though not complete, is legible and 
consistent. From the latest to the earliest 
of its chapters the story is capable of clear 
*See an interesting and suggestive paper by Pro- 
fessor Le Conte on ‘ Critical Periods in the History of 
the Earth,’ Bull. Dept. Geology, University of Califor- 
nia, Vol. I. (1895), p. 313; also one by Professor 
Chamberlin on ‘ The Ulterior Basis of Time-divisions 
and the Classification of Geological History,’ Journal 
of Geology, Vol. VI. (1898), p. 449. 
