Page:A Treatise on Geology, volume 2.djvu/301

 CHAP. X. near the west side of New Zealand. On this line it is nearly all sea. The distribution of land and water presents little symmetry; yet a meridian at right angles to that above noticed leaves, east and west of it, nearly equal masses of land. The poles are believed to be situated in the midst of extensive oceans, though the progress of modern research has augmented our knowledge of antarctic land. These circumstances, though they indicate little of symmetry in the rugged and irregular surface of the globe, supply some points not unimportant. The general spheroidal figure of the earth is obviously not the result of superficial waste and minute arrangements, as the hypothesis of the invariability of natural forces would seem to require; on the contrary, this figure appears clearly due to the general conditions of the interior masses, which are only marked and rendered irregular by the changes that have happened at the surface. Upon the Leibnitzian supposition, that the crust of the globe is cooled over an ignited nucleus, which is still further undergoing refrigeration, it appears possible to understand the accumulation of water about the poles, since, in the direction of the polar diameter, the contraction of bulk would be in no degree balanced by the augmented centrifugal force, corresponding to a determinate velocity and a diminished diameter. But, on the supposition of the spheroidal earth having been originally a sphere, and having derived its actual figure from superficial processes, the polar regions should have been very elevated land, and the equatorial zone deep sea. This neither is, nor appears to have been, the case.

Again, the remarkable contrast of a hemisphere of land opposing one of sea marks very clearly the influence of some great and general alterations of surface level. The supposition of a cooling globe undoubtedly meets this case; but it appears difficult to see how the rival speculation can be applied to phenomena on so vast a scale, even if unlimited time be given to the operation of "modern causes."