This detail from a picture of the Southwell frigate shows the crew putting three enslaved Africans into the longboat to take them to the ship. A slave ship often spent months moving along the coast, buying one or two enslaved people at a time until the captain had bought the number he was ordered to carry. In the late 1700s, Bristol captains often went to the large trading town of Calabar, where the local merchants could supply larger numbers quickly, making for a faster voyage and thus greater profit.