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On July 4, 1858, one of America’s fastest racing yachts departed Charleston, South Carolina, to a chorus of saluting cannons. Crowds along the waterfront waved flags and handkerchiefs as Wanderer slipped away from the shore with the triangular pennant of the prestigious New York Yacht Club flapping proudly in the breeze. In spite of the send-off, the speedy schooner wasn’t destined for another regatta. Instead, on a day when the United States celebrated its independence, the Wanderer was off on a voyage across the Atlantic Ocean to deprive hundreds of their freedom.

A little more than two months later, William Bowden, commander of the British warship HMS Medusa, peered through his spyglass and spotted the sleek American yacht in the mouth of the Congo River. On patrol along the African coastline in search of illegal slave ships, Bowden boarded Wanderer and was struck by its opulence—gilded mirrors, rosewood furniture, satinwood cupboards, ornamental brasswork and “all that could be desired for comfort and luxury,” as the New York Times reported. At the invitation of the Americans, British officers dined on fine damask linens in the salon and sipped champagne and smoked cigars on the deck as Captain John Egbert Farnum regaled them with tales of his adventures in the Mexican-American War and serving as a guerrilla fighter in Nicaragua and Cuba.

Toward the end of the evening, Farnum jokingly asked his guests if they wished to inspect the yacht to ensure it wasn’t a slave ship. The British officers laughed at what seemed a preposterous idea for surely no vessel that extravagant would be used in the slave trade. The prestige of the New York Yacht Club banner that continued to fly from Wanderer’s main mast, however, shrouded its odious mission for hidden from view were supplies that Wanderer took on in Charleston—chains, handcuffs and enough Georgia pine to build a secret slave deck.

As soon as the British departed, the Americans resumed their vile—and illegal—work building pens in which to squirrel away human cargo. Congress voted to abolish the slave trade in 1807 and made it a crime punishable by death in 1820. Wanderer’s Southern owners, however, had little regard for federal laws. New York Yacht Club member William Corrie and Charles Lamar, a member of a prominent Southern family, purchased the one-year-old ship from Louisiana sugar magnate John D. Johnson in the spring of 1858 and immediately set about retrofitting one of the quickest yachts of its day into a slave ship.

Explore the Mapping Slave Voyages interactive to find out more about the 350-year history of the transatlantic trade.

Among a group of pro-slavery radicals known as “fire-eaters,” Corrie and Lamar supported Southern secession and wanted the international slave trade reopened. Even if American law banned the importation of slaves, the fire-eaters wished to prove the impotence of the federal government to stop them. As the New York Times described, the radicals believed that if arrested they could “trust to the laxity of officials, the defects of proof, the technicalities of the law, and especially the sympathy of jurors, for escape from punishment.”

As Wanderer’s elaborate retrofit progressed in Port Jefferson, New York, a customs official grew increasingly suspicious—especially when extra-large water tanks capable of holding 15,000 gallons were hauled aboard and Farnum, a known troublemaker, was spotted in the town. The New York Times wondered aloud whether the yacht might be transformed into a slave ship but acknowledged how absurd the notion was “that a vessel so costly, and so well adapted for a gentleman to spend his elegant leisure in, should be selected as a slaver.” Government officials ordered the ship to New York City for a thorough inspection. Although there was such a volume of supplies that “showed that an extraordinary voyage of some kind was contemplated,” nothing could specifically implicate the vessel as a slave ship. Customs officials had no choice but to let it proceed to Charleston and onto Africa where in exchange for rum, gunpowder, cutlasses, muskets and other goods, the Southerners secretly purchased nearly 500 slaves—many of them teenage boys—and branded them with hot irons.

After riding wind and waves across the Atlantic Ocean, Wanderer dropped anchor at Jekyll Island off the coast of Georgia on November 28, 1858, with 400 African slaves. Approximately 70 of those held in bondage died in the brutal conditions and foul air of the ship’s hold during the six-week journey. The slavers quickly smuggled their human cargo ashore in small boats and scattered them in plantations and slave markets across the South, where they were sold for upwards of $700 a head.

Reports quickly surfaced, however, of the presence of newly imported slaves from West Africa. Within weeks, authorities had arrested the ringleaders of the criminal enterprise—including Corrie and Lamar—and charged them with slave trading, piracy and other offenses. The defendants stood trial in federal court in Savannah, Georgia, in the summer of 1860, but the result was much as the fire-eaters had imagined. The Southern jury refused to convict their peers, a verdict that further inflamed sectional tensions that burst into the Civil War the following year. Ultimately, the harshest sanction leveled on the conspirators was Corrie’s expulsion from the New York Yacht Club.

Lamar bought the ship back at a quarter of its value, but the United States seized it as an enemy vessel in May 1861 and converted it into a Union gunboat that participated in naval blockades of Confederate ports before sinking off the coast of Cuba in 1871 after a return to commercial use.