Penny Blood: Serial Sensation and Working-Class Entertainment — page 166: what you’re looking at

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

cH. x1.] THE REVELATIONS OF THE PLUMB-LINE. 149 contract and become more dense. This argument is answered by Mr Whitley's experiments’, and is contrary to Walters- hausen’s most reasonable theory* that the successive couches increase in density according to their chemical composition. (3) If every protuberance outside a thin crust must be accom- panied by a protuberance inside down into the fluid mass, then wherever there is a hollow as in deep seas in the outward surface, there must be one also in the inner surface of the crust corresponding to it; thus leading to a law of varying thickness which no process of cooling could have produced. But we appeal to a mode of action, namely compression, which is quite capable, in the case of a crust not perfectly soft and compres- sible, of producing such surface hollows® and corresponding downward protuberances, as we have explained in the preceding chapter. In spite however of these three objections, which the Archdeacon believed to be fatal to the form in which the Astronomer Royal offered his explanation of a deficiency of matter below the mountains, the Archdeacon adopts in the remainder of this paper another form of the same theory, appa- rently preferring it altogether to his former hypothesis of an increased ellipticity for the Indian arc. We have thus established our assertion that the roots of the mountains can be felt by means of the plumb-line. The converse proposition ought to be true, that where the land is not elevated above the sea, there the heavier substratum ought to be within a less distance of the surface, and the conse- quence ought to be that attraction at the surface should be greater. This also is known experimentally to be the case. The subject is discussed by Archdeacon Pratt in the fourth edition of his Figure of the Earth. He establishes the fact, but raises upon it theoretical conclusions not warranted by geology. There can however be no doubt that he has demonstrated the existence of increased density beneath the oceans. He says ‘in fact the density of the crust beneath the mountains must be less than that below the plains and still less than that below the 1p, 23. 2p. 28. 3p. 133, GONG oOo SS (CO)