BACHE, HARTMAN (1797-1872), American engineer and army officer, was born in Philadelphia, Pa., in 1797. He graduated at West Point in 1818 and entered the engineer corps of the army, retiring as a brevet brigadier-general in 1867. He made numerous topographical and hydrographic surveys but is particularly remem bered for his achievements as an engineer. He directed the con struction of the Delaware breakwater and the Brandywine light house and was successful in applying the iron screw pile in marine foundation work. He died in Philadelphia on Oct. 8, 187 2.