The Proprietors of Locks and Canals on the Merrimack River is a limited liability corporation founded on June 27, 1792, making it one of the oldest corporations in the United States.
The company was founded for the purpose of constructing a transportation canal, the Pawtucket Canal around the Pawtucket Falls on the Merrimack River in what was then known as East Chelmsford, Massachusetts. Over a mile long with four lock chambers, the Pawtucket canal was finished in 1796. Although the canal allowed for lumber and other goods to be transmitted from New Hampshire to the shipyards of Newburyport, the competing Middlesex Canal, a direct route to Boston, opened just ten years later, ruining the Pawtucket's business.
In 1821, The Boston Manufacturing Company of Waltham, Massachusetts, purchased the charter of the Proprietors of Locks and Canals, incorporated it into the new Merrimack Manufacturing Company. In the early 1820s, the Pawtucket canal became a major component of the Lowell power canal system. with the founding of the textile industry at what became Lowell.
In 1825, the corporation was reorganized again and separated from the Merrimack Manufacturing Company, under the leadership of Kirk Boott. This allowed the city of Lowell to grow quickly, as many other manufacturing corporations were founded in Lowell to take advantage of the waterpower sold by the Proprietors of Locks and Canals. Paul Moody was one of their first chief engineers. In the mid-19th century, the company was under the leadership of James B. Francis, inventor of the Francis Turbine, who took over when George Washington Whistler left to work on Russia's railway system.
James Hayward Harlow (1846 - 1892) was chief engineer from 1856 until his death in 1892.