Answered

The closeness of the place, and the heat of the climate, added to the number in the ship, which was so crowded that each had scarcely room to turn himself, almost suffocated us. The air soon became unfit for respiration from a variety of loathsome smells, and brought on a sickness among the slaves, of which many died . . . The shrieks of the women, and the groans of the dying, rendered the whole a scene of horror almost inconceivable.

What is the main idea described in the text?