162 
MR. ROBERT MALLET ON VOLCANIC ENERGY. 
must be ascribed to forces which acted (along with these or before them) upon a 
vast if not universal scale, and at far greater depths beneath the existing surface.] 
53. It is a remarkable fact that the western coasts of nearly all the great masses of 
land are the steepest, and that even without reference to littoral ranges of mountain, 
such as the Andes or those of the Malabar coast*. 
Now this is just what we should expect if the ocean -bed were the result of the 
depression of the surface of the spheroid by the deformation supposed ; for the 
matter in the crust that descended, having a velocity of rotation due to its higher 
radius (that prior to depression), would, in descending to the level of the ocean-bed, 
tend to fall (and by so much of the energy of its whole mass of matter to push) to the 
eastward of the true vertical, just as a weight let drop from a height falls to the 
eastward of the vertical. This effect would be greater as the deformation was more 
rapid, but would never disappear while it occupied some finite time. [The rapidity of 
elevation has at all times depended upon the rate of refrigeration ; and the latter, 
whatever its actual rate at any given epoch, must have been greater as the temperature 
of the earth’s surface was higher as compared with space. Thus, when the temperature 
of the surface was, let us suppose, 1500° Fahr., the annual rate of elevation of great 
mountain-chains may have been considerable.] If, on the contrary, the continents were 
raised up by some inconceivable force of elevation, no such phenomenon would present 
itself ; and it seems impossible to see how this could have occurred without the 
production of vast cavities beneath. 
54. These sudden contrary flexures at the junctions of the continents and sea-basins 
initiated lines of fracture and of weakness in the early crust, along which we find 
ranges of mountains and volcanic action now. 
55. The ocean-bed deformation took place most probably long before the surface- 
temperature was such as to admit of its being filled with a permanent ocean water, 
though probably for a long period depositions of boiling water, at an enormously high 
boiling-point, took place locally and in basins here and there, beginning towards the 
poles, alternately boiling away and being redeposited, and being thus attended with 
torrential rains and with great surface-currents and deluges of hot water. 
56. To the solvent power of these and to their violent carrying and denuding action and 
prodigious powers of breaking up the rocky mass of the primordial crust, by comparatively 
sudden heating, by the continued conduction from below (in antagonism with the sudden 
cooling locally), by precipitation of comparatively cold water from above, must be ascribed 
powers of comminution and alternate denudation and deposition such as later geologic 
time, much less historic time, presents us with nothing but the faintest resemblance of. 
And to this early machinery may be ascribed the production, as by a mighty mill, 
* Dana (American Journ. Sci. 1847) has, however, shown a different possible cause for the greater prevalent 
steepness of mountain-ranges on one of their flanks, viz. the greater intensity of the tangential pressure at the 
less steep flank, or smaller resistance of the materials of the opposite one. This, however, gives no solution 
cf the very general fact of western flanks being the steepest. — March 1873. 
