^{page 107 note 1} Scrivenor, J. B., Min. Mag., vol. xiii, p. 348, 1903;Google ScholarThomas, H. H., Q.J.G.S., vol. lxv, p. 232, 1909;Google ScholarSmellie, W. R., Trans. Geol. Soc. Glasgow, vol. xiv, p. 267, 1911–1912.Google Scholar

^{page 107 note 2} Economic Geology, vol. vii, p. 697, etc., 1912.Google Scholar

^{page 107 note 3} Hatch, & Rastall, , Sedimentary Rocks (London, 1913); Appendix by T. Crook, p. 350.Google Scholar

^{page 109 note 1} Richards, R. H., Ore-Dressing, 1906, tables in Appendix.Google Scholar

^{page 109 note 2} Exclusive of such local sands, etc., such as those bordering the granite masses of Devon and Cornwall. These sands may be full of tourmaline, etc.

^{page 109 note 3} See, for example, the recently published Professional Paper 86, U.S.G.S., “The Transportation of Débris by Running Water” (G. K. Gilbert).

^{page 110 note 1} Since the above was written Professor W. G. Fearnsides has read a paper before the British Association upon the Underground Contours of the Barnsley Seam (Geol. Mag., October, 1915, p. 465). See also “The Use of Thickness Contours in the Valuation of Lenticular Coal Beds” (Rogers, G. S. and Lesher, C. E.): Econ. Geology, vol. ix, p. 707, 1914.CrossRefGoogle Scholar

^{page 110 note 2} Professor E. Hull used the term isodiametric (or isometric) lines, as those joining points of equal thickness of a formation before denudation had acted upon it. See Q.J.G.S., vol. xviii, p. 127, 1862.Google Scholar

^{page 110 note 3} C. S. Slichter, “Motions of Underground Water”: Water Supply and Irrigation Papers, No. 62, U.S.G.S. Hazen's ‘Uniformity Coefficient’ obtained by sifting is not satisfactory, and is applicable only to coarse deposits.