216 
THE PHYSICAL GEOGRAPHY OF THE SEA. 
The microscope, under the eye of Ehrenberg, has enabled us 
158) to put tallies on the wings of the wind, to learn of them 
somewhat concerning its " circuits." 
Now, may not these shells, which were so fine and impalpable 
that the officers of the Dolphin took them to be a mass of unctu- 
ous clay — may not, I say, these, with other specimens of sound- 
ings yet to be collected, be all converted by the microscope into 
tallies for the waters of the diiFerent parts of the sea, by which 
the channels through which the circulation of the ocean is car- 
ried on are to be revealed ? 
Suppose, for instance, that the dwelling-place of the little shells 
which compose this specimen from that part of the ocean be ascer- 
tained, by referring to living types, to be the Gulf of Mexico or 
some other remote region ; that the habitat and the burial-place, 
in every instance, be far removed from each other — by what agen- 
cy, except through that of currents, can we suppose these little 
creatures — themselves not having the powers of locomotion — to 
come from the place of their birth, or to travel to that of their 
burial? 
Man can never see — he can only touch the bottom of the deep 
sea, and then only with the plummet. Whatever it brings up 
thence is to the philosopher matter of powerful interest ; for by 
such information alone as he may gather from a most careful ex- 
amination of such matter, the amount of human knowledge con- 
cerning nearly all that portion of our planet which is covered by 
the sea must depend. 
Every specimen of bottom from the deep sea is, therefore, tc 
be regarded as probably containing something precious in the wa}* 
of contribution to the sources of human knowledge. 
