[197] Phil. Mag. for May, 1868.
[198] Student’s “Elements of Geology,” p. 91. Second Edition.
[199] In an interesting memoir, published in the Phil. Mag. for 1850, Mr. Alfred Tylor estimated that the basin of the Mississippi is being lowered at the rate of one foot in 10,000 years by the removal of the sediment; and he proceeds further, and reasons that one foot removed off the general surface of the land during that period would raise the sea-level three inches. Had it not been that Mr. Tylor’s attention was directed to the effects produced by the removal of sediment in raising the level of the ocean rather than in lowering the level of the land, he could not have failed to perceive that he was in possession of a key to unfold the mystery of geological time.
[200] Proc. Roy. Soc., No. 152, 1874.
[201] I have taken for the volume and mass of the sun the values given in Professor Sir William Thomson’s memoir, Phil. Mag., vol. viii. (1854).
[202] Phil. Mag., § 4, vol. xi., p. 516 (1856).
[203] Phil. Mag. for July, 1872, p. 1.
[204] “Principles,” p. 210. Eleventh Edition.
[205] “Principles,” vol. i., p. 107. Tenth Edition.
[206] The conception of submergence resulting from displacement of the earth’s centre of gravity, caused by a heaping up of ice at one of the poles, was first advanced by M. Adhémar, in his work “Révolutions de la Mer,” 1842. When the views stated in this chapter appeared in the Reader, I was not aware that M. Adhémar had written on the subject. An account of his mode of viewing the question is given in the Appendix.