330 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
At the bottom of the seas, side by side with the continuous work of 
natural forces—of gravity, of chemical precipitations and dissolutions— 
-myriads of beings live and die, innumerable generations succeed each 
other and develop to finally accumulate inert deposits, which in later 
millions of years shall become the sedimentary formations of a new 
land just as to-day in Touraine, in Normandy, in Champagne the 
chalky limestones which nourish our crops and from which we extract 
material for the construction of our houses are the product of bryozo- 
ans, of foraminifera of the Cretaceous age. <A glance at the geolog- 
ical formations which make up the solid substratum of our arable land 
is enough by the presence of innumerable remains of marine shells to 
establish the fact that the greater part of these chalk beds were formed 
in the seas. Beside these marine sediments the lake, river, and other 
sediments play but a minor part. And if in comparison with the 
sedimentary deposits proper we considered the formations due to an- 
other great source of terrestrial activity—fire—we could show, dis- 
regarding the plutonic rocks, that the evidences of these igneous 
rocks occupy a limited area at the surface. It is true that the plu- 
tonic rocks would soon predominate if we could dig down a short dis- 
tance into the crust of the globe. At a depth of 2 or 3 kilometers 
(which appears to us enormous because we are very small and because 
our tools are very insufficient, but which is only a shallow depth in 
the 6,400 kilometers of radius of the earth), we should find the sedi- 
ments would disappear, giving place almost exclusively to igneous 
rocks. But this geology of the depths, which perhaps will be the 
geology of our successors, unfortunately is not yet for us. And if 
one is limited as we are to the surface of the earth, the part played 
by the waters, especially by the marine waters, becomes absolutely 
predominant. 
Geology was made by the waters; it was made by the seas. If 
water, as it is passing away in other worlds, had not existed at the 
surface, this geology would be altogether different; and the day 
when active water shall have disappeared from the surface of the 
earth, which may happen, though perhaps only by congealing, the 
land will be dead; its geological history, as we understand it at least, 
will be ended. 
Thus oceanography permits us to see in operation before us this 
work of the waters, which has played such a preponderant part in the 
construction of the earth’s crust. There are some sediments, com- 
parable to those of geological strata, which are now in process of for- 
mation in the seas, just as the scenery prepared in the mysterious 
places beneath the stage of a theater is caused at a given moment 
to spring up to alter the scene. Of the method of these great changes 
at which we can not be present, but of which the ancient equivalent 
constitutes our geologic history, oceanography informs us. ‘The 
