This model shows a typical ship in the early 1700s on the Middle Passage. To preserve their profits, captains and sailors tried to limit the deaths of slaves from disease, suicide, and recolts. In the grisly arithmetic of the slave trade, captains usually chose between two options: pack in as many slaves as possible and hope that most survive, or put fewer aboard, improve the conditions between decks, and hope to lose fewer to disease. (Photo: Ken Lu ? Wikimedia Commons / This file is licensed under the Creative Commons Attribution 2.0 Generic license.)