Penny Blood: Serial Sensation and Working-Class Entertainment — page 191: what you’re looking at

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

174 AMOUNT OF COMPRESSION. [cu. x11. Making this substitution we obtain from (3), E(¥') 3 (X= (4-3 By} - Ha And substituting this value in (5), ae _ BL mrke= E= - (4) - 3 (B)} K-18 8045-305); whence _fe 7 2 (A’) —> (B’) a rica Sark r. wp Ld ~ (r—k} o — p 827k" If we can estimate & (A’) —> (B’) and Zé we shall now be able to find e for any assumed value of &. Let us pause to consider what the symbols involved import. If we regard the compression to arise solely from diminution of volume beneath the cooled crust, and not from the ex- tension of the crust itself, then e is the mean coefficient for the compression of the whole crust, which has arisen from this cause since the existing mequalities began to be formed. If however we neglect the contraction of the matter of the crust itself, which for a thickness of 20 miles or so the results of Chapter VI show that we may do, then the coefficient of compression for the crust will be the same as that of contraction for the sphere. We do not know exactly the laws which govern, either the contraction of the matter of the crust, nor yet those which determine the rate at which it thickens through solidification. But it is evident that the compression of the surface must be greater than the mean compression. For the remaining symbols r is the present radius, & is the mean thickness of the crust, considered of equable density, that is to say, it is the thickness which the crust would have, if it had been perfectly compressible, so that the contraction of the globe should not have caused it to be wrinkled or thickened anywhere. COMIC OOOKS.EO