THE SALTS OF THE SEA. 
165 
of the universe by virtue of its saltness, and which it could not 
perform were its waters altogether fresh. And thus philosophers 
have a clew placed in their hands which will probably guide them 
to one of the many hidden reasons that are embraced in the true 
answer to the question, " Why is the sea salt ?" 
329. Sea Shells. — We find in sea water other matter besides 
common salt. Lime is dissolved by the rains and the rivers, and 
emptied in vast quantities into the ocean. Out of it, coral islands 
and coral reefs of great extent — marl-beds, shell-banks, and in- 
fusorial deposits of enormous magnitude have been constructed by 
the inhabitants of the deep. These creatures are endowed with 
the power of secreting, apparently for their own purposes only, 
solid matter, which the waters of the sea hold in solution. But 
this power was given to them that they also might fulfill the part 
assigned them in the economy of the universe. For to them, 
probably, has been allotted the important office of assisting in 
giving circulation to the ocean, of helping to regulate the cli- 
mates of the earth, and of preserving the purity of the sea. 
330. The better to comprehend how such creatures may influ- 
ence currents and climates, let us suppose the ocean to be per- 
fectly at rest — that throughout, it is in a state of complete equi- 
librium — that, with the exception of those tenants of the deep 
which have the power of extracting from it the solid matter held 
in solution, there is no agent in nature capable of disturbing that 
equilibrium — and that all these fish, &c., have suspended their se- 
cretions, in order that this state of a perfect aqueous equilibrium 
and repose throughout the sea might be attained. 
In this state of things — the waters of the sea being in perfect 
equilibrium — a single moUusk or coralline, we will suppose, com- 
mences his secretions, and abstracts from the sea water 293) 
solid matter for his cell. In that act, this animal has destroyed 
the equilibrium of the whole ocean, for the specific gravity of 
that portion of water from which this solid matter has been ab- 
stracted is altered. Having lost a portion of its solid contents, it 
has become specifically lighter than it was before ; it must, there- 
fore, give place to the pressure which the heavier water exerts to 
push it aside and to occupy its place, and it must consequently 
travel about and mingle with the waters of the other parts of the 
ocean until its proportion of solid matter is returned to it, and 
