41 
the countries which are now inhabited. . . . Btit the 
countries now inhabited, which had been laid dry by that 
last revolution, had been inhabited before, if not by man, 
yet at least by land animals. It follows that preceding 
revolutions — one at least — had buried these regions beneath 
the water." May not all the phenomena disclosed by 
Geology — in denudation of surface ; alternate depression 
and eleviition of vast areas ; depositation of layer after layer 
of sedimentary strata ; erosion of the great valleys ; in fact, 
formation of our mountains, as the macerated bones of 
primeval plateaux, disrupted, torn down, and excavated by 
aqueous action, with all noted chmatal revolutions, including 
glacial epochs, — be referable to, and, on sound principles of 
natural philosophy, only lucidly explained by the simple 
though heretofore overlooked material first cause — change of 
the earth's centre of gravity >. The earth being spherical, 
having an unstable fluid envelope, resting within the 
hollows and irregular surfaces of the external crust, which 
is apparently " standing in the water, and out of the water," 
is subject, as to the extent and relative x^osition of its areas 
of land surfaces, to the interchanges of position and re- 
arrangements of volume of its oceanic envelope, tending to 
apparent elevation or depression of land with reference to 
ocean level, which must result inevitably from operation of 
the imperative natural law of gravitation of the fluid enve- 
lope, so as that its exterior shall present a surface, horizontal 
at each point of radius vertical to the earth's centre of 
gravity, and thus only maintains an equilibrium ; — continuous 
change of centre calling into action the diurnal tide wave. 
It has been frequently asserted by those delighting to turn 
the edge of reasoning aside by flippant jestings, that I hold 
and assert the idea of such an extended polar apex as to 
constitute a pear or lemon-shaped earth, by polar ice accu- 
mulation. But such extension of apex is an unnecessary 
fiction. Any extension of the polar radius by ice would 
necessarily affect the equilibrium of the sphere, though of 
small bulk compared with the equatorial bulge assumed by the 
astronomer, as causing the earth's tilt by stellar attraction. 
Altitude of ice continents, and of sea surfaces, are ascertain- 
able by the barometer, and it would be a most interesting 
subject for scientific investigation, if, by competent observers, 
and finely graduated instruments, the relative rise and de- 
pression of oceanic surfaces, at rest, all over the world, could 
fee contemporaneously recorded, at successive periods, after 
lapse of stated numbers of years. " The assumption that the 
earth is an oblate spheroid, or orange-shaped, was suggested 
