THE SALTS OF THE SEA. 167 
there a portion of its solid contents ; it therefore becomes spe- 
cifically lighter, and up it goes, ascending to the top with in- 
creased velocity, to take the place of the descending column, 
which, by the action of the winds, has been sent down loaded 
with fresh food and materials for the busy little mason in the 
depths below. 
334. Seeing, then, that the inhabitants of the sea, with their 
powers of secretion, are competent to exercise at least some de- 
gree of influence in disturbing equilibrium, are not these crea- 
tures entitled to be regarded as agents which hav6 their offices to 
perform in the system of oceanic circulation, and do not they be- 
long to its physical geography ? It is immaterial how great or 
how small that influence may be supposed to be ; for, be it great 
or small, we may rest assured it is not a chance influence, but it 
is an influence exercised — if exercised at all — by design, and ac- 
cording to the commandment of Him whose "voice the winds and 
the sea obey." Thus God speaks through sea-shells to the ocean. 
335. It may therefore be supposed that the arrangements in 
the economy of nature are such as to require that the various 
kinds of marine animals, whose secretions are calculated to alter 
the specific gravity of sea water, to destroy its equilibrium, to be- 
get currents in the ocean, and to control its circulation, should 
be distributed according to order. 
336. Upon this supposition — the like of which nature warrants 
throughout her whole domain — we may conceive how the marine 
animals of which we have been speaking may impress other fea- 
tures upon the physical relations of the sea by assisting also to 
regulate climates, and to adjust the temperature of certain lati- 
tudes. For instance, let us suppose the waters in a certain part 
of the torrid zone to be 70°, but, by reason of the fresh water 
which has been taken from them in a state of vapor, and conse- 
quently by reason of the proportionate increase of salts, these wa- 
ters are heavier than waters that may be cooler, but not so salt 
35). 
This being the case, the tendency would be for this warm, but salt 
and heavy water, to flow off as an under current toward the Polar 
or some other regions of lighter water. 
Now if the sea were not salt, there would be no coral islands 
to beautify its landscape and give variety to its features ; sea- 
