In brief, to guard against insurrection the captains made the conditions of life so cruel that the slaves were fairly forced to revolt.
In 1759 a case of an uprising that was happily successful was recorded.
The slaver "Perfect," Captain Potter, lay at anchor at Mana with one hundred slaves aboard.

The mate, second mate, the boatswain, and about half the crew were sent into the interior to buy some more slaves.
Noticing the reduced numbers of their jailors, the slaves determined to rise.

Ridding themselves of their irons, they crowded to the deck, and, all unarmed as they were, killed the captain, the surgeon, the carpenter, the cooper, and a cabin-boy.

Whereupon the remainder of the crew took to the boats and boarded a neighboring slaver, the "Spencer." The captain of this craft prudently declined to board the "Perfect," and reduce the slaves to subjection again; but he had no objection to slaughtering naked blacks at long range, so he warped his craft into position and opened fire with his guns.

For about an hour this butchery was continued, and then such of the slaves as still lived, ran the schooner ashore, plundered, and burnt her.
[Illustration: "THE ROPE WAS PUT AROUND HIS NECK"] How such insurrections were put down was told nearly a hundred years later in an official communication to Secretary of State James Buchanan, by United States Consul George W.Gordon, the story being sworn testimony before him.