The Quarterly journal of the Geological Society of London . rtical or very high. At the southern end of the section thegrit is almost black, and this peculiar variety crops out on theopposite slope about 50 yards to E. by a little S. The strikes agreetherefore in a general way with the usual strikes of the volcanicrocks in the Cardington mass. See the accompanying map, facingp. 120. The other locality is in the quarries at Woodgate, where is exposedthe clear series of rhyolites and grits described in my 1879 paper{op. cit. p. 658). These rocks are admitted by Prof. Blake to belongto the true v
The Quarterly journal of the Geological Society of London . rtical or very high. At the southern end of the section thegrit is almost black, and this peculiar variety crops out on theopposite slope about 50 yards to E. by a little S. The strikes agreetherefore in a general way with the usual strikes of the volcanicrocks in the Cardington mass. See the accompanying map, facingp. 120. The other locality is in the quarries at Woodgate, where is exposedthe clear series of rhyolites and grits described in my 1879 paper{op. cit. p. 658). These rocks are admitted by Prof. Blake to belongto the true volcanic group. I have recently detected at the back ofthis quarry, at the western extremity, and almost on the strike ofthe green grits, a reddish grit, composed of quartz and red felspar,with some bits of rhyelite. In hand-specimens it is seen to be quiteof the ordinary Uriconian type. The annexed section (fig. 2) showsthe relation of the grits of these two localities to the associatedvolcanic rocks. Eig. 2.—Section across the Hope-Bowcller mass. N. g. Grit (b) Caer Caracloc.—The mass of grit near the south-western endof the ridge is regarded by Prof. Blake as a mere is, however, very clear proof that it is intercalated in theUriconian. In one place it is distinctly bedded. The reddishvariety alternates in regular seams with a dark grit, with a shalyband, and with a fine-grained compact rock, like halleflinta, butwhether igneous or aqueous is uncertain. Prof. Bonney inchnes tothe former belief. These beds dip very clearly to the Both above and belownumerous exposures of the ordinary hiillefiinta of the district are seento crop out, with the same dip, or, where the dip is not apparent,with a strike to or (c) Charlton Hill.—Clearer evidence for the pre-Cambrian age ofthe grits and conglomerates could hardly be desired *. After Prof. * Quart. Journ. Geol. Soc. vol. xxxv. (1870) p. finr,; vol. xlii. (I88li) p. 483. 116 DR. CH. CALLAWA
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