Note 210 — Chapter XIII · THE ERUPTIONS OF LLANDEILO AND BALA AGE
Reading edition
Mem. Geol. Survey, vol. iii. 2nd edit. pp. 137, 139.
[211] Bala Volcanic Series, pp. 41, 71, 72, 123.
[212] Mr. Greenly has made a sketch map of this interesting locality. As he has now established his home in North Wales, I trust he may find an opportunity of returning to Y-foel-frâs and completing his investigations.