...river from the upper. If the Federals could cut through this neck, they could avoid the Confederate works and move on up the river by boat as far as the works at Chaffin's Bluff and Drewry's Bluff. Captain Peter S. Michie , of the United States Engineers, later a brigadier-general, was detailed to dig a canal through at Dutch Gap. This would cut off four and a half miles of river. The excavation was forty-three yar...