This produced copious perspirations, so that 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, thus falling victims to the improvident avarice, as I may call it, of their purchasers.
This was mentioned before that they would load the ships with so many slaves that they barely had space that led to many diseases and resulted in many slaves to die.