Robert Fulton
The first successful trial run of a steamboat had been made several years earlier in the United States by inventor John Fitch, on the Delaware River on August 22, 1787. Attendees included delegates from the Constitutional Convention, who were observing while taking a break from their summer-long sessions at Independence Hall. The steamboat was propelled by a bank of oars on either side of the boat. The following year Fitch launched a boat powered by a steam engine driving several stern-mounted oars. These oars paddled in a manner similar to the motion of a swimming duck's feet. With this boat he carried up to thirty passengers for hire on numerous round-trip voyages on the Delaware River between Philadelphia and Burlington, New Jersey.
Daniel French (inventor)
In 1807 Robert Fulton placed on the Hudson River the steamboat "North River" (aka "Clermont") which was powered by a low pressure Boulton and Watt steam engine. The heavy and inherently inefficient engine required an increase in the size, and hence the weight, of the steam cylinder for an increase in power. Mounting the cylinder vertically, Fulton "invented" a complex series of levers and cranks to transmit the power of the piston to each paddle wheel crank. Two paddle wheels, one on each side, were mounted midway between the bow and the stern. On the western rivers, Fulton's design was the standard for steamboats until the "Enterprise" which was designed by French.