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.
Steamboats of the Colorado River
In November 1852, the "Uncle Sam", a 65-foot long side-wheel paddle steamer, also built by Domingo Marcucci, became the first steamboat on the Colorado River. It was brought by the schooner "Capacity" from San Francisco to the delta by the next contractor to supply the fort, Captain James Turnbull. It was assembled and launched in the estuary, 30 miles above the mouth of the Colorado River. Equipped with only a 20 horsepower engine, the "Uncle Sam" could only carry 35 tons of supplies, taking 15 days to make the first 120 mile trip. It made many trips up and down the river, taking four months to finish carrying the supplies for the fort, improving its time up river to 12 days. Negligence caused it to sink at its dock below Fort Yuma, and was then washed away before it could be raised, in the spring flood of 1853. Turnbull who meanwhile had returned to the Delta from San Francisco with another cargo and a more powerful engine for the "Uncle Sam". He returned for a new hull, while the army sent wagons to recover the cargo from the delta again. However, Turnbull in financial difficulty, disappeared from the city leaving creditors unpaid. Nevertheless, Turnbull had shown the worth of steamboats to solve Fort Yuma's supply problem.