The worst maritime disaster in US history was not the Titanic but the Sultana, a wooden steamboat whose boilers exploded on the Mississippi at two in the morning in April 1865, killing up to 1,700 people. Most were Union soldiers freed from prison camps such as Andersonville, packed aboard far past legal capacity, and the news was buried beneath the hunt for John Wilkes Booth. The episode traces how steam reached the water: Newcomen’s atmospheric engine, James Watt’s double acting cylinder, and the high pressure engines of Oliver Evans and Richard Trevithick that were light enough for a boat and prone to burst, since crews had no reliable pressure gauges.

John Fitch ran a commercial steamboat on the Delaware in 1788 but lost out to good wagon roads, and William Symington’s Charlotte Dundas towed two 70 ton barges into a headwind in 1803. Robert Fulton won the credit in 1807 with a Boulton and Watt engine and a Hudson River monopoly secured with Robert Livingston. Ocean crossings waited for fuel efficient compound engines, while on western rivers flat bottomed boats cleared the forests for fuel, silting the Mississippi and worsening its floods.

• The SS Savannah crossed the Atlantic in 1819 with 75 tons of coal and 25 cords of wood but mostly used its sails.
• Early ocean steamers gave up to 40 percent of their cargo space to fuel.
• The Panama steamer route cut the gold rush trip to San Francisco from 160 days to about 40, and the SS California arrived with around 400 aboard a ship built for 200.
• Stranded riverboats were walked over sandbars by grasshoppering, levering the bow up on spars with a steam winch.
• Mary Millicent Miller became the first woman to earn a steamboat master’s license in 1884, and Callie Leach French held both pilot and master licenses.