Autograph Letter Signed, to Thomas Sopwith, mining engineer, discussing at some length his patented method for raising water from mines, recently described in a pamphlet. 3 pp. 7 x 4½ inches, leaves separated, neatly trimmed. Lower Mersey Vein, Bootle Bay, Liverpool, 15 February 1840. Henry Adock, civil engineer, compiler of Adcock’s Engineers’ pocket-book, which appeared each year, took out patents for improvements in docks and quays.