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The continents having sunk, how havethey risen again to their present level ?

After all this subsidence and elevation,how happens it that of the strata whichwere deposited horizontally so many re-main horizontal ?

How happens it that subsidence and ele-vation were unattended by fracture ?

Hut the submersion of the earth is notthe only condition required to bring abouta state of things such as we have de-scribed. Valleys could never have beenexcavated, nor huge bowlder-stones havebeen transported to so great a distanceunder water, had the water been subjectto such comparatively trifling agitationsonly, as those by which that fluid is af-fected in the present constitution of theworld.

To the solution of the problem Impetuo-sity of Motion in the water is indispensible;but an increased Quantity of water is, per-haps, superfluous ; for there seems no goodreason for supposing, that the quantitywhich actually subsists upon the earth, ifthrown into a state of excessive agitation,

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