It may have been in or near the village of
Manmoel in the Upper Sirhowy valley.
Most in that area seem to working in the iron works (from
National Gazetteer, 1868):
"MAMHOLE, (or Manmoel), a hamlet in the parish of Bedwellty, lower division of the hundred of Wentllooge, county Monmouth, 7 miles N.W. of Pont-y-pool. It is situated near the Monmouth canal, between the rivers Rumney and Sirhowey. The inhabitants are chiefly engaged in the coal and iron works which are extensively carried on. The district is very populous."
