Penny Blood: Serial Sensation and Working-Class Entertainment — page 70: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

cH. v.] ELEVATIONS AND DEPRESSIONS. 53 A little consideration will give the following geometrical relation: The volume of the Sea above the datum level = the area of the whole surface of the globe x the depth of the datum level below the sea-level — the volume of rock displacing water between those levels. Let S = area of the Sea. D =its mean depth. JL = area of the Land. W = volume of the Land above the sea-level. d=the depth of the datum level below the surface of the Sea, considering these as parallel. Now the volume of rock displacing water between the datum level and the sea-level will be %(A)— W, and since in the case supposed % (A) = 87rr*ke, we shall obtain the following relation: SD =(S + L)d —(8mrke — W). - But it is to be observed that this relation assumes the sur- face of the ocean to be everywhere parallel to the datum level, which is itself supposed to be parallel to the original surface of the globe when it was first covered with a solid crust. But the distribution of the great continents and oceans, as well as observations on the plumb-line, render it probable that there is some cause which increases the density beneath the great oceans, and tends to accumulate the water upon them, so that their depth is greater than it would be, were that solely due to a relative depression or locally diminished curvature of the sea-bed. Let us then call X the accumulated volume of water in excess of that which the oceans would contain, were their sur- face parallel everywhere to the datum level; retaining D as the observed mean depth of the sea, but using d as measured from the supposed surface as just defined. In order to allow for the accumulated water, we must correct GONG oOo SS (CO)