The ubiquitous Mississippi river steamboat was invented because the Mississippi, despite it’s breadth and length, was not, (until dredging by the Army Corps of Engineers in the 20th c.), particularly deep. This is also true of the Ohio and the Missouri – the two major ‘feeder’ rivers for the Mississippi.
A paddle-wheel steamboat is a flat-bottomed boat – it sits ‘high’ in the water, with a a wide, flat hull. Steam drives the pistons that then turn the wheel or wheels. Steamboats are either “paddle-wheelers” -referring to one large wheel at the back of the boat – or “side-wheelers” – referring to two smaller wheels placed at the sides of the boat. In either case, the wheels turn and the paddles push the boat along the river.
Being a riverboat sailor was not easy – one had to know the river well, because the Mississippi is a constantly (if slowly) changing river of sandbars and snags. In addition to the risk of running aground, there was also the risk of fire and explosion from the steam engines. (Some of the more spectacular demises of riverboats were depicted in popular prints in Victorian times!) Among those who plied the river was a young pilot by the name of Samuel Clemens, who, when he began to write, used the river term for a water depth of 2 fathoms – “Mark Twain” – as his nôm de plume.
The flat bottom steamboat made brisk trade up and down the Mississippi and Ohio possible – allowing goods made in Cincinnati to be sold in New Orleans – or even shipped overseas! You can still see a good number of working steamboats in major ports along the Mississippi and Ohio – though many today have been converted into casinos.
Click on the image to see it / download it full-sized.
P.S. Not all steamboats were riverboats – some had deeper hulls for sea or lake travel. Many of the passenger boats on the Great Lakes were steamboats.