Sunny South was an extreme clipper, the most uncompromising kind: every line of her hull sacrificed cargo capacity for raw speed. On her maiden voyage she ran from New York to San Francisco in 143 days, around the storm-lashed tip of South America, and made unusually fast time in the Pacific. She crossed to Hong Kong in 51 days and came home to New York in 102. For a ship to be this fast in an age of sail was to be valuable in ways both honest and not. The same hull that won races could also outrun a navy. By the late 1850s, with the transatlantic slave trade outlawed by the major powers and hunted by patrol ships, speed had become the single most prized quality in a slaver. A fast ship could slip a blockade. Sunny South was among the fastest afloat.

Around 1859 she was sold, renamed Emanuela, and sent into the illegal trade out of Havana, reputedly the swiftest slave ship sailing from that port. What that role meant in human terms is unbearable to read plainly. On the morning of 10 August 1860, in the Mozambique Channel, the British naval sloop HMS Brisk sighted a ship trying to slip away through the haze and gave chase. Brisk drove on under sail and steam, building to eleven and a half knots, and it took four hours of hard pursuit before she drew close enough to fire a shot across the other vessel's bow. Aboard the captured ship were 846 enslaved Africans. More than half were children. They had been forced into the hold of a vessel designed to carry tea and silk, and 105 of them had already died on the passage; 741 were still alive when the Royal Navy boarded.

The explorer John Hanning Speke, a passenger aboard Brisk, walked through the captured ship and could not forget it. Below decks he found people half-starved, mostly children, and a few old women dying in air so foul he struggled to describe it. Some of those with strength left were tearing at the hatches to reach the salted fish stored beneath. Six months later, with the ship held in port, the novelist Charles Dickens visited and reported that no amount of scrubbing had driven out the smell. These were not statistics. They were sons and daughters and elders torn from their homes, and the historical record, written by the men who freed them, preserves at least the shape of their suffering. The survivors were eventually put ashore at Mauritius, where, in a bitter irony, many were bound over as indentured laborers to the island's sugar planters. Freedom, for them, came with conditions.

Justice, such as it was, fell unevenly. The slaver's 45-man crew were simply discharged to shore, and Brisk's captain, Algernon de Horsey, wrote an indignant letter to the Admiralty protesting that the men who ran this trade should escape unpunished. The ship herself was condemned as a prize, taken into the Royal Navy, and converted into a store vessel renamed Enchantress. Her story ended where so much of it had played out, in the waters off East Africa. On 20 February 1861 she ran onto a reef near Mayotte in the Mozambique Channel. By one account she was sailing so fast that her crew did not realize they had already run eleven miles off course. The navy burned the wreck where she lay. The most beautiful ship of her generation finished her days as a charred hull on a coral reef, a few hundred miles from where the people she had carried were first set free.