Shannon, a S. E. county of Missouri, intersected by Current river; area, about 1,150 sq. m.; pop. in 1870, 2,339, nearly all white. The surface is uneven, and partly occupied by pine forests. Mines of copper and iron are worked. The chief productions in 1870 Were 7,243 bushels of wheat, 104,725 of Indian corn, 7,496 of oats, 9,045 lbs. of tobacco, 3,294 of wool, 25,129 of butter, and 4,812 gallons of sorghum molasses. There were 637 horses, 657 milch cows, 1,658 other cattle, 2,549 sheep, and 6,362 swine. Capital, Eminence.
Shannon, the largest river of Ireland, rises at the foot of Mt. Cuilcagh in the N. W. part of the county Cavan, flows S. W. for a few miles to Lough Allen, thence by a circuitous but generally S. course to Lough Derg, passing through Lough Ree, and thence S. S. W. to Limerick, below which the river, here called the Lower Shannon, flows W. S. W. through a broad estuary to the Atlantic. Its total length is about 250 m. Portions of its course are very picturesque. Its largest affluent is the Suck, which enters it from the west between Loughs Ree and Derg; others are the Boyle, Fergus, Inny, Brosna, Mulkear, and Maig. The principal towns on its banks besides Limerick are Leitrim, Carrick, Athlone, and Killa-loe. The tides in the estuary of the Shannon vary between 14 and 18 ft., and vessels of 400 tons can ascend as far as Limerick; the navigation has been improved throughout the entire length at a cost of about £500,000, and parliament in 1874 appropriated £300,000 for its further improvement; and canals connect it with many parts of Ireland.