Great Western Railway > Monmouthshire and Brecon Canals (Canal Numbers 95 and 95A) > Water supply to the canal
"Reservoirs (Safety Provisions) Act, 1930. Prescribed form of record relating to a Reservoir [Penyvan near Aberbeeg]"
Details include: water levels; average rainfall; structural character of dam or walls. Book No 1 1933-1945.