When work on the Erie Canal began in 1817, little was known about canal engineering, and construction depended on the ingenuity of many people. Canvass White, a surveyor, greatly facilitated canal construction by perfecting a meagre limestone that could be used to form a mortar which hardened under water. His discovery of this abundant, easily prepared waterproof cement immensely improved construction techniques. The Erie was a practical school for acquiring engineering knowledge. Resourceful contractors, surveyors, and local workmen planned the canal through a wilderness. They drove stakes, bored holes, felled trees, pulled stumps, blasted rocks, and dug in swamps. They built canal banks, towpaths, waste weirs, culverts, aqueducts, locks, and gates. When they finished in 1825, they had constructed a 363-mile canal across the state. It was considered the foremost engineering achievement of the time. Western New York flourished with new, cheap transportation. The canal ensured the place of New York City as the nation's greatest port and city, and it hastened development of the Mid-West. The modernized State Barge Canal System, consisting of the Erie, Champlain, Oswego, and Cayuga-Seneca Canals, was completed in 1918.