The Geology of the Meldon Valleys near Okehampton, on the Northern Verge of Dartmoor

The area covered by these notes comprises as much of the watershed of the West Okement and the Redaven as lies between the London & South-Western Railway-line on the north and, on the south, the ‘Roof of Devon,’ the Yes Tor-High Wilhays ridge; practically it is yet further restricted, since but brief reference is made to the granite-mass of Dartmoor. The rivers and brooks within this area have been useful section-cutters in a country where, for many acres, stray boulders on grassland are the only other guides, and their assistance has been more marked since the great flood of August 14th, 1917, which not only swept their beds clear, but tore away from the banks their cover of grass and heather. Artificially, also, much has been done to reveal the rock-structure. A very extensive quarry is worked by the railway company east of Meldon Viaduct, the face of this quarry being some 600 yards long. Formerly limestone was raised south of the railway both on the eastern and on the western banks of the West Okement; but both quarries are now abandoned. During the last eight or nine years stone has been taken from the dyke of the Meldon aplite east and west of the Redaven, and two small quarries in the same rock were opened several years ago on the flank of South Down, while prospecting work has been executed near the old Ice House on Sourton Tors. There is a quarry in the shales by the Vellake, and