High-pressure steam boilers were the deadliest technology of the mid-19th century. They powered industry, transportation, and warfare, and they blew up with appalling regularity. John Ericsson's answer was the caloric engine, which replaced pressurized steam with heated air. The principle was elegant: compress air into a reservoir, heat it to increase pressure, admit it to massive working cylinders, and let the expanding air drive the pistons. A key innovation was the regenerator, a wire mesh heat exchanger designed to capture heat from the exhaust air and use it to warm the incoming supply, theoretically recycling energy and maximizing fuel efficiency. Ericsson convinced a group of investors led by John B. Kitching to form the New York and Havre Company and finance the ship's construction at a cost of approximately $500,000 -- an enormous sum for the era.

On January 11, 1853, the Ericsson steamed from New York Harbor to Sandy Hook with members of the press and the New York City Council aboard. The four working cylinders, paired with four supply cylinders of 11.5 feet in diameter, drove the ship's side-mounted paddle wheels at a speed of roughly 8 knots. By the standards of the day, it was a modest pace, and the massive engines -- with their 6-foot piston strokes -- occupied a disproportionate share of the vessel's interior. The demonstration proved the mechanical principle: hot air could indeed propel a ship. But the ratio of engine bulk and weight to the power produced made the caloric engine commercially impractical. Steam engines of comparable size generated far more thrust. The revolutionary idea worked; it just did not work well enough.

In April 1854, the Ericsson encountered a squall near Jersey City while returning from a trip to Washington, D.C. A coal port had been left open to facilitate waste removal, and the vessel took on water and sank in the shallow harbor. It was an ignominious end for a ship that had attracted national attention, but the shallow depth meant salvage was possible. The Ericsson was raised and converted to conventional steam power, the caloric engines replaced by the very technology they had been designed to supplant. Under steam, the ship served reliably if unremarkably for decades. John Ericsson himself moved on to other projects, most famously the USS Monitor, the ironclad warship that fought the CSS Virginia at Hampton Roads in 1862 and changed naval warfare forever.

The Ericsson's final chapter played out far from New York Harbor. Sailing under a different name after her conversion, the vessel met her end when she was blown aground at the entrance to Barkley Sound on the west coast of Vancouver Island, British Columbia. This stretch of coastline, known grimly as the Graveyard of the Pacific, has claimed hundreds of ships over the centuries. Treacherous currents, sudden fog, shallow reefs, and violent storms make the approaches to Barkley Sound one of the most hazardous passages on the Pacific coast. The ship that had been built to demonstrate the future of maritime propulsion became just another wreck on a shore littered with them. But the idea behind the caloric engine survived. Variations of the hot air engine -- notably the Stirling engine -- would find applications in the 20th and 21st centuries, long after the wooden hull that first tested the concept had rotted away on a British Columbia beach.