Note 230 — Chapter XIII · THE ERUPTIONS OF LLANDEILO AND BALA AGE
Reading edition
Quart. Journ. Geol. Soc. vol. xliv. (1888), p. 517. See his further remarks in Geol. Mag. 1891, p. 483.
[231] The Amlwch slates exhibit on a great scale the puckering that points to intense compression. This "gnarled" structure, as Prof. Hughes called it, has been illustrated by Mr. Harker, British Assoc. Report (1885), pp. 839, 840.