In Africa, 40% of the captured blacks died during the displacement up to the coast, and other 10% or 20% where they were housed ,in the port, before  embarks . More of the half,  would die in Africa.That fact transform the slaves in an expensive merchandise, and the traffic a very lucrative activity.

When  they arrive in Brazil, they were transported in ships called tumbeiros. They were brought piled in the basements of the ships, and on the average  came from 300 to 500 men, women and children, traveling separated. A lot of times the ship shipwrecked due to the load excess. They came shackled or arrested two to two to avoid rebellions and to impede that  they threw themselves in the sea. Most of the time the food and the water were scarce and rotten. There was not ventilation nor sanitary instalations. It was a true torture.They suffer and  many of them died (about 20% )during the crossing.