Penny Blood: Serial Sensation and Working-Class Entertainment — page 89: what you’re looking at

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

7/2 ELEVATIONS ON THE HYPOTHESIS OF SOLIDITY. - It is desirable to know what the radial contraction of the globe would have been, that is, how much nearer to the centre any point on the surface would be at present, than it was when solidification took place. In this case we must find the con- traction along a radius. But we must also remember that any point on the surface must be considered raised by the average height due to the compression which results from the sph ericity of the surface, t.e. by 2ke. Now the contraction along any radius will evidently be E [% 5 |. Pnde, 3 Jo if as before we take 2a as the depth to which the cooling, and therefore the contraction, is sensible. Hence the actual con- traction will be E [* E | 3], nda — 2ke =" (V2a— ab x 1273820) — 2ke. If we give to V the value 7000°F., and = = 000007, with the value just found for a this gives radial contraction = 11112 — 866 feet, = 10246 feet, = 1-9 miles. If however we assume 4000° for the temperature of solidifi- cation, since the result is proportional to Va, and therefore to V*, we get in this case, in which 2ke= 149 feet, radial contraction = 3479 feet, = 0°65 of a mile. p. 264. If such be the case with the earth’s. crust, then the temperature would increase more rapidly, and the depth at which we might suppose the tempera- ture of solidification to be reached would be nearer the surface. This would make the average height of the elevations less. commiclsoolkks (CO)