Penny Blood: Serial Sensation and Working-Class Entertainment — page 130: what you’re looking at

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

CH. 1x.] CRUST NOT FLEXIBLE. 113 Now a negative conclusion of this kind is far from being without importance ; for it is by a method of exhaustion that we are best able to attack our problem. What then are the assumptions upon which we have arrived at this unsatisfactory result? They are, that the crust is (1) thin, and (2) flexible, and (3) that it rests on a liquid substratum. Of these assump- tions the first cannot be wrong. The crust is no doubt thin as compared with the other dimensions with which we have to deal; as, for instance, the width of a continent. That it rests on a@ fluid substratum has been already shown to be almost certain. It remains then that the error in our assumptions lies in supposing the crust flexible. It follows that, when a horizontal pressure acts upon a tract of crust, we must not suppose that the yielding will take place by the bending of the crust, while its uniform thickness 1s maintained ; for, if that were the case, an arrangement of anticlinals, bearing a close resemblance to the result of our investigation, would be produced. But we must rather suppose that the yielding takes place through a crushing together and thickening of the crust. The consequence will be that elevations above the datum level will be accompanied by depressions beneath. The anti- clinals will not be filled with fluid from below, but will be the upper portions of double bulges, which will dip into the fluid below as well as rise into the air above. And this is the condition of things with which we shall attempt to deal in the following chapter. COMMUC NOO SS (CO)