Penny Blood: Serial Sensation and Working-Class Entertainment — page 135: what you’re looking at

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

118 DISTURBED TRACT. (ou. x. viz. 2°68, and the subjacent fluid of the density of basalt, viz. 2°96," we have, : : 2(a)—2%(b) _o-—p ——¢ = 0'l 04, =(8)- =) p or about 7,. The diminution of density by elevation of tempe- rature need not be regarded *. We have thus far had under consideration the relations of the elevations and depressions above and below the mean levels, as they would depend upon the conditions of equilibrium of a mass of any form, floating without external constraint upon a fluid, so far as the vertical forces are concerned. We must however also consider how much importance belongs to the attachments of the tract at its extremities AC and BD; and on this account, and from our general ignorance of the amount of rigidity which must be attributed to the mass, it is obvious that we can only arrive at the most general conclusions. Let us then suppose as before, that the portion of crust AbdC is compressed into the position ABDC. The lateral pressure will act in some straight line drawn from a point in AC toa corresponding point in BD, Consequently it will have no ten- dency to open any fissures in the crust. We may therefore dismiss from consideration such a condition of things as is represented in our second figure of the diagram, p. 46. If the crust were flexible and elastic, such a form as that represented in the first figure might be possible. But the con- dition more in accordance with natural appearances is that it is partially plastic and partially brittle. It is capable of with- standing considerable pressure until it gives way, but when it does so, the harder portions will break up, and the plastic accommodate themselves among the interstices of the harder. 1 Calculating from Laplace’s law of density, = at the surface=0-00000058, y being expressed in feet. Consequently the increase to p in 20 miles would be 0:056 and the density of Basalt would be met with at 100 miles. But Laplace’s law is empirical, and does not give information as to the actual arrangement of the successive couches. 2 Note, p. 68. commiclsoolkks (CO)