What century were the Leiper Canal and Duluth Ship Canal built?
Leiper Canal Early in the 19th century, the Leiper Canal built in 1828-29 during the middle of the American canal age ran about 3 mi along Crum Creek in Delaware County to its mouth in Eastern Pennsylvania's Delaware Valley carrying its owners quarried products to docks on the Delaware River tidewater until 1852.
American Ship Building Company The American Ship Building Company was the dominant shipbuilder on the Great Lakes before the Second World War. It started as Cleveland Shipbuilding in Cleveland, Ohio in 1888 and opened the yard in Lorain, Ohio in 1898. It changed its name to the American Ship Building Company in 1900, when it acquired Superior Shipbuilding, in Superior, Wisconsin; Toledo Shipbuilding, in Toledo, Ohio; and West Bay Shipbuilding, in West Bay City, Michigan. With the coming of World War I, the company also acquired Buffalo Dry Dock, in Buffalo, New York; Chicago Shipbuilding, in Chicago, Illinois; and Detroit Shipbuilding, in Wyandotte, Michigan. American Shipbuilding ranked 81st among United States corporations in the value of World War II military production contracts.