I thought someone would ask:
ROMAN MINE, Draethen, Glamorganshire. Bristol Exploration Club Caving Report No 15 by J & N Tuck, July 1971. 50pp fold out survey in rear.4 b & w plates, numerous line drawings. Many other mines in the area are also described. Quarto, needless to say, long out of print and in great demand. SB
Cutting coal in my spare time.