CHESAPEAKE AND OHIO CANAL, in the United States, connects Cumberland, Md., with Washington, D.C., and is used largely for the transportation of coal from the Cumber land region to the Potomac river. It has 73 locks, gaining an elevation of 609 feet. The cost of construction with improvements was about $14,000,000. It is 184 m. long, 68 ft. wide and 6 ft. in depth with capacity for canal boats of 18o tons.