the foundations of the sea beyond the depth of two or three thousand feet. Should future deep-sea soundings establish this as a fact in other seas also, it will prove of the greatest value to submarine telegraphy. What may be the thickness of this cushion of still water that covers the bottom of the deep sea is a question of high interest, but we must leave it for future investigation.
603. The conservators of the sea.—In Chapter X. (The Salts of the Sea), I have endeavoured to show how sea-shells and marine insects, may, by reason of the offices which they perform, be regarded as compensations in that exquisite system of physical machinery by which the harmonies of nature are preserved. But the treasures of the lead and revelations of the microscope present the insects of the sea in a new and still more striking-light. We behold them now, serving not only as compensations by which the motions of the water in its channels of circulation are regulated and climates softened, but acting also as checks and balances by which the equipoise between the solid and the fluid matter of the earth is preserved. Should it be established that these microscopic creatures live at the surface, and are only buried at the bottom of the sea, we may then view them as conservators of the ocean; for, in the offices which they perform, they assist to preserve its status by maintaining the purity of its waters.
604. The anti-biotic view the most natural.—Does any portion of the shells which Brooke's sounding-rod brings up from the bottom of the deep sea live there; or are they all the remains of those that lived near the surface in the light and heat of sun, and were buried at the bottom of the deep after death? Philosophers are divided in opinion upon this subject. The facts, as far as they go, seem at first to favour the one conjecture nearly as well as the other. Under these circumstances, I incline to the anti-biotic hypothesis, and chiefly because it would seem to conform better with the Mosaic account of creation. The sun and moon were set in the firmament before the waters were commanded to bring forth the living creature; and hence we infer that light and heat are necessary to the creation and preservation of marine life; and since the light and heat of the sun cannot reach to the bottom of the deep sea, my own conclusion, in the absence of positive evidence upon the subject, has been, that the habitat of those mites of things hauled up from the bottom of the great
