On the evidence afforded by fossil plants, as to the boundary line between the Devonian and Carboniferous rocks / by Samuel Haughton.

  • Haughton, Samuel.
Date:
1855
Catalogue details

Licence: Public Domain Mark

Credit: On the evidence afforded by fossil plants, as to the boundary line between the Devonian and Carboniferous rocks / by Samuel Haughton. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    principles I regard as so obvious, and so generally received, that I shall not waste the time of the Society by further enforcing them, but shall proceed to my task of examining the fossil plants of the lower fossiliferous beds, in order to ascertain whether it is possible to draw a line separating them into Devonian and Carboniferous; and if the result of that examination should be, that no such line can be drawn, then we are entitled, in accordance with the second principle laid down, to draw the boundary line at the base of the fossiliferous beds. Some geologists of reputation are of opinion, that the first inti'o- duction of land plants on the earth took place at the close of the De- vonian and commencement of the Carboniferous period; and explain the occurrence of anthracitic and bituminous beds in the Silurian rocks of Ireland, Scotland, and Russia, by the hypothesis, that they are the result of accumulations of marine plants. As this question was one of some interest, I undertook lately the chemical examination of the ash of the anthracite, described by Dr. Whitty as occurring, in the county of Cavan, in Silurian slates. For the purpose of comparison, I have placed beside my results the results of two specimens of ash of Newcastle coal, examined by H. Taylor, Esq. :— GOOD NEWCASTLE IMPURE NKWCASTLE COAL. COAL. Ash =1-3G per cent Ash = IG 'JO per cent. Silica, 69-56 G4-21 Alumina, 12-19 28-78 Peroxide of Iron, .... 15-96 2-27 Lime, 91)9 1-34 Magnesia, 1-13 l.|2 I'otush, 1-17 2-28 Soda, — 100-00 100-00 SILUELAN ANTHRACITE, COUNTY OF CAVAN. Ash=4-28 per cent-. Silica, Alumina and Peroxide of Iron, Lime, Magnesia, Sulphate of Potash, Sulphate of Soda, Sulphates of Lime and Magnesia, Alkalies in combination with Silex ; Carbon; and Loss, 71-43 19 81 0- 43 1- 34 0-28 0- 23 1- 22 5-2G 100-00