Question: What century were the Leiper Canal and Duluth Ship Canal built?
Context: A ship canal is a canal especially intended to accommodate ships used on the oceans, seas or lakes to which it is connected, as opposed to a barge canal intended to carry barges and other vessels specifically designed for river and/or canal navigation.  Because of the constraints of accommodating vessels capable of navigating large bodies of open water, a ship canal typically offers deeper water and higher bridge clearances than a barge canal of similar vessel length and width constraints. The Tralee Ship Canal (Irish: "Long Chanáil Trá Lí" ) is a canal built for freight and passenger transportation from Tralee Bay to the town of Tralee in County Kerry, Ireland.  The canal fell into disuse in the mid-20th century but has since been restored. Manchester Ship Canal Police (also known as Manchester Dock Police and the Port of Manchester Police) was a police force in the United Kingdom that was responsible for policing the Manchester Ship Canal.  It was maintained by the Manchester Ship Canal Company between 26 December 1893, when the canal opened, and 31 January 1993. The Duluth South Breakwater Inner Light is a lighthouse on the south breakwater of the Duluth Ship Canal in Duluth, Minnesota, United States.  It forms a range with the Duluth South Breakwater Outer Light to guide ships into the canal from Lake Superior. The Duluth South Breakwater Outer Light is a lighthouse at the end of the south breakwater of the Duluth Ship Canal.  It forms a range with the Duluth South Breakwater Inner Light. 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. The Port of Manchester was a port in North West England, until its closure in 1982.  It was created as a customs port on 1 January 1894, four months before the official opening of the Manchester Ship Canal.  It extended along the whole 36 mi length of the ship canal, from Eastham in the west to Manchester in the east, absorbing the Port of Runcorn, which had been created in 1862.  The creation of the new port moved the Port of Liverpool's boundary 11 mi to the west.  The ship canal transformed Manchester from a landlocked city into a major sea port, at its height the third-busiest port in the United Kingdom.  Once delivered to the port goods could be transported to other parts of the country such as Leeds to the east, and up to 100 mi south as far as Birmingham. The Duluth Ship Canal is an artificial channel cut through Minnesota Point, providing direct access to Duluth harbor from Lake Superior.  Begun privately in 1871, it was put under federal supervision and maintenance several years later.  It is still an important component of the harbor facilities. The Duluth North Pier Light is a lighthouse on the north breakwater at the entrance to the Duluth Ship Canal. The Manych Ship Canal is a canal system between the basins of the Sea of Azov, Black Sea, and Caspian Sea.  Proposals are being considered to expand the system into a larger Eurasia Canal system.  The canal would be a multipurpose water-resources system and an important part of the national transport system serving internal and international Caspian oil traffic, with huge economic potential for the region.  A proposed design would enlarge the Manych Ship Canal to a depth of 6.5 m and width of 80 m with traffic capacity for more than 75 million tons per year.  This proposed Eurasia Canal would allow passage of vessels with a freight-carrying capacity of up to 10,000 tons.  Russia's unique geographic location and transportation infrastructure does not correspond economically to the current logistics of Russian and foreign trade.
Answer: 19th century