The shipwreck was found off Cape Romain in about 40 feet of water, the underwater archaeologist and treasure hunter told Discover News this week.
"We have positively identified the vessel through the engine type, length, width, type of decking and other construction features, as well as its location, which matches perfectly with historical accounts," Spence said.
He said the iron-hulled steamer is "in surprisingly good condition with most of the ship relatively intact and sitting upright."
The 1,028-ton, 216-foot, 5-inch vessel was built in Scotland in 1881 and named the Craigallion. It sank a first time in the Bahamas in 1885. It was raised and renamed the Ozama.
"The vessel made a number of trips to Panama and other ports in the Caribbean, sailing into turbulent times," Spence said.
"Her colorful history is packed with events such as a mutiny and extensive gun and money smuggling to Haiti."
A December 1888 article in The New York Times reported the Ozama was carrying "1,000 stands of arms, 3 Gatling guns and 500,000 cartridges to Cape Haytien" it said likely were bound for Haiti for use by the troops of the island nation's embattled president.
Another Times article stated the Ozama carried $300,000 in paper money to Haiti.
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