SS Hippocampus

Hippocampus (US official number 11819) was a diminutive wooden passenger and package freighter, built by shipwright George Hanson in St. Joseph, Michigan, in 1867.^[1][2] Her hull had an overall length of 90 feet 1 inch (27.5 m), and a length between perpendiculars of 82 feet (25.0 m).^[3] It was 17 feet (5.2 m) in beam, and 8 feet (2.4 m).^[3] One source lists the dimensions of Hippocampus' hull as 100 feet (30.5 m) in length, 20 feet (6.1 m) in beam, and 7 feet (2.1 m) in depth.^[2] Her tonnage was calculated as either 153 gross register tons.^[2] Additionally, she was rated 90 tons burthen.^[4] Her propulsion system consisted of a 150 hp (110 kW) steam engine with a piston stroke of 22 inches (0.6 m), manufactured by the Vulcan Iron Works of Chicago, Illinois.^[2][5] The Chicago Tribune reported her cargo capacity as 80,000 feet (24,384.0 m) of lumber.^[3]

Built for Bouton, Shaw & Morrison of St. Joseph, at a cost of $23,000 (equivalent to $450,240 in 2024^[a]), Hippocampus was named after the Greek phrase for seahorse.^[1][3][6] After her launching on 16 July 1868, she was towed to Chicago, by the steamer Lady Franklin, arriving on 18 July. In Chicago, Hippocampus was surveyed by officials from the local custom house.^[3] She was enrolled at Grand Haven, Michigan, on 16 September 1867, and her home port was St. Joseph.^[2][5]

In 1867, Hippocampus began hauling fruit from St. Joseph, and Benton Harbor, Michigan, for Milwaukee, Wisconsin.^[2][3] On 10 October that year, Hippocampus reportedly became the first steam-powered vessel to enter the harbour of Manitowoc, Wisconsin, from which tri-weekly voyages to Milwaukee, were subsequently advertised by The Manitowoc Pilot.^[b][7]

On the night of 7 September 1868, Hippocampus left Benton Harbor, Michigan, her decks piled with several thousand boxes of peaches, and 55 passengers and crew aboard.^[6] After being towed to St. Joseph, she departed for Chicago. Early the following morning, a squall swept Lake Michigan, sinking Hippocampus, and killing 26 people. Contemporary newspapers speculated overloading to be a contributing factor to her loss.^[6][8]

26 people died in the sinking, with the survivors being rescued by the scow Trio.^[2] Her loss represented the single largest loss of life within the fruit trade of southwestern Michigan.^[1]

In late-April 1877, the clerk of the steamer Messenger reported that a fishing smack had snagged their nets on a submerged object in about 100 feet (30.5 m) of water, roughly 20 miles (32.2 km) from St. Joseph.^[9][10] A contemporary article by The Inter Ocean reported the confirmation of the object as the wreck of Hippocampus based on the discovery of peach boxes, and other items known to have been on board, entangled in the nets of the fishermen who initially discovered it.^[10] Plans involving a Chicago-based salvage firm were made to raise the wreck, though they never materialised, and its location was eventually lost.^[1][11]

As of 2026, the wreck of Hippocampus has not been located.^[1] In 2018, the Associated Press listed her as "one of the most-sought-after undiscovered Great Lakes shipwrecks".^[12]