No, the prisoners don’t work in the quarries – most of the dartmoor quarries closed from 1880 through to 1940s, Foggintor (I think) around 1910. I’m not aware of any working quarries or mines on dartmoor now, apart from the clay workings on the west side (mostly outside but some inside) and the mothballed Meldon, but go back 150 years and it was heaving.
