I've been looking at a series of small quarries located in granite beds in the James River, Virginia, USA. There are drill holes, blast holes, and feather and wedge holes. There's a stone that was split off bedrock using feathers and wedges, the piece is about 3 feet long, by 18" high by 18" deep and apart from being split off the parent rock, hasn't moved. On it are one set of horizontal holes on the west and south faces. They are set three abreast about 6" down from the top, each being about 3" long, half an inch high and cut at a perpendicular to the vertical face. They go back into the rock about 3" and taper inward slightly and are more or less flat across the back end.
Any ideas on what these things do for a living?
Thanks in advance,
Lyle Browning
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