A Conduit leading to a ? Mine

Drawing, 'A Conduit leading to a ? Mine / A rough wooden fence' by John Sell Cotman (1782-1842), pencil on paper, 26 Jul 1800; 11.5 cm x 26.2 cm; inscription in pencil recto lower right 'July 26 1800'; inscription in brown ink lower right numbered '73'; mark stamped upper right part of circular stamp 'Depart(ment of Practical Art)No(rwich)'