Note 240 — Chapter XIII · THE ERUPTIONS OF LLANDEILO AND BALA AGE
Reading edition
Quart. Journ. Geol. Soc. vol. xxxi. (1875) p. 408, vol. xxxii. (1876) p. 24. Geology of Northern Part of Lake District (Mem. Geol. Survey), p. 22. In a subsequent paper the more basic lavas of Eycott Hill are compared with dolerites (Monthly Microscopical Journ. 1877, p. 246).
[241] These rocks were mapped as tuffs by Mr. Ward. Their microscopic characters have been described by Messrs. Harker and Marr, Quart. Journ. Geol. Soc. xlvii. (1891), p. 292; by Mr. Harker, op. cit. p. 517; and by Mr. W. M. Hutchings, Geol. Mag. 1891, p. 537; 1892, pp. 227, 540.