Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/390

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This order of succession I had already determined when my attention was directed to the paper before mentioned, on the geology of the country near Ripon, by the Rev. John Stanley Tute ; the following is the series further north as drawn out by him : —

Red grit of Knaresborough, South Stainley, and Scarab, capping "most of the hills eastward as far as Pateley, and the lower beds of which form the Brimham Rocks."

Cayton-Gill beds, consisting of three beds beneath the red grit. " The uppermost consists of thin flags full of the remains of Encrinites. The second abounds with the casts of Brachiopoda and other organic remains. The lowest is an exceedingly hard and fine sandstone, mottled with carbonaceous markings."

"Arenaceous flags and coal-measures; immediately below these last beds is a series of shales, flags, and sandstones, of considerable thickness, all more or less stained with iron."

The succession of the Cayton-Gill beds below the red grit seemed to me at once to agree with what I had found near Spofforth; and soon after, in company with Mr. Aveline and Mr. Green, I visited these beds north of Ripley ; and here we found, as round Spofforth, the first and second beds of red grit, followed by the shell-bed, and this again by the hard Follifoot grit. I afterwards found precisely the same succession just north of Harrogate, the red grit of Knox Farm and Killinghall being succeeded by a hard sandstone containing Encrinites and Brachiopods, striking east and west, with a northerly dip from Four Lane Ends to Saltergate Hill, and having the hard white Follifoot grit dipping regularly under it. During a hurried visit I paid to the celebrated Brimham Rocks, I found on the flanks of the hill below them both the shell-bed and the hard white grit cropping out, thus confirming in my mind the conclusion at which the Eev. Stanley Tute had arrived as to the crags being formed of the lower parts of the Plumpton grit — though here, be it observed, the peculiar red and purple tint is absent. If, now, we sum up the evidence both for and against the Permian age of these red beds, we find —

Against this age : —

1. Their similarity in structure to millstone -grit beds proper, and their complete dissimilarity to beds of supposed Rothliegende age elsewhere in England.

2. Their occurrence only in a millstone-grit area.

3. The unconformity of the overlying magnesian limestone to these beds.

4. Their complete conformity to the underlying undoubted mill- stone-grit rocks.

5. Their containing apparently similar plants to the ordinary millstone -grit beds.

6. Their being of a red colour, as is by no means uncommon in grits of the millstone-grit series.

For their Permian age : —

1. Their likeness to certain German Rothliegende conglomerates.

2. Their purplish tint in parts — the colour of many shales and