^{page 165 note 2} Mem. Geol. Survey, vol. ii. pt. i. p. 102.Google Scholar

^{page 165 note 3} Siluria, 1859, p. 23.

^{page 166 note 1} The Carboniferous Limestone and Cefn-y-fedw Sandstone of North Wales Morton, G. H., F.G.S., p. 21.Google Scholar

^{page 166 note 2} The Coal-fields of Great Britain, by ProfessorHull, E. , 2nd ed. p. 99.Google Scholar

^{page 166 note 3} I have seen at least ten instances where the Carboniferous Limestone during period of its formation had been locally raised above the sea-level, and had thus be exposed for a time to atmospheric action and erosion. In eight of the examples to beds of coal were formed, either resting immediately on the sculptured surface, or a bed of clay which covered it; the thickest amounts to about a foot, at lngleto others varied down to a mere film of carbonaceous matter in the clayey depos Subsidence taking place, the deposition of the limestone again progressed to a great extent. The methods of weathering go to prove that the limestone had become consolidated previously to its elevation and erosion; in some cases shrinkage join are present, and are filled with calcite, which stands out in relief on the eroded so face; the condition of these small joints indicates that the limestone must he become solidified before being raised above the sea-level, prior to the formation of the coaly beds. In some instances angular or weathered fragments of limestone a embedded in the clayey deposit which fills hollows in the surface of the limestone.

^{page 166 note 4} They have been described in an Essay by ProfessorHughes, T. McK., “On the Break between the Upper and Lower Silurians of the Lake District,” Geol. Mag. Vol. IV. p. 346.Google Scholar

^{page 167 note 1} Report on the Probability of the Occurrence of Coal in the Vicinity of Lancaster, 1837.

^{page 167 note 2} Principles of Geology, 10th edit. vol. i. p. 453.Google Scholar

^{page 167 note 3} The Earth's Physical Evolution, The Penn Monthly, 1876, p. 424;Google Scholar also a resumé of the same, by Fisher, Rev. O., Geol. Mag. Dec. II. Vol. III. p. 374Google Scholar.

^{page 169 note 1} Quart. Journ. Geol. Soc. vol. xxvii. p. 105.Google Scholar

^{page 169 note 2} The Ninth Bridgewater Treatise, Appendix, p. 222.

^{page 169 note 3} Origin of Mountains, p. 109.

^{page 170 note 1} Theory of the Earth, by Hutton, James, M.D., F.R.S.E., 1795, vol. i. p. 123.Google Scholar

^{page 170 note 2} Proc. Geol. Soc. vol. ii. p. 73Google Scholar; Quart. Journ. Geol. Soc. vol. iii. p. 186Google Scholar.

^{page 170 note 3} Origin of Mountain Ranges, by Reade, T. Mellard, C.E., F.G.S., p. 326.Google Scholar

^{page 170 note 4} Page 10.

^{page 170 note 5} Physics of the Earth's Crust, p. 82.