The hardships and inconveniences suffered by the negroes during the passage, are scarcely to be enumerated or conceived.  They are far more violently affected by the sea-sickness than the Europeans. It frequently terminates in death, especially among women.  But the exclusion of the fresh air is among the most intolerable.  For the purpose of admitting this needful refreshment, most of the ships in the slave-trade are provided, between the decks, with five or six air-ports on each side of the ship of about six inches in length, and four in breadth; in addition to which, some few ships, but not one in twenty, have what they denominate wind-sails.  But whenever the sea is rough, and the rain heavy, it becomes necessary to shut these, and every other conveyance by which the air is admitted.  The fresh air being thus excluded, the negroes rooms very soon grow intolerably hot.  The confined air, rendered noxious by the effluvia exhaled from their bodies, and by being repeatedly breathed, soon produces fevers and fluxes, which generally carries off great numbers of them.

During the voyages I made, I was frequently a witness to the fatal effects of this exclusion of fresh air.  I will give one instance as it serves to convey some idea, though a very faint one, of the sufferings of those unhappy beings whom we wantonly drag from their native country, and doom to perpetual labor and captivity. Some wet and blowing weather having occasioned the port-holes to be shut, and the grating to be covered, fluxes and fevers among the negroes ensued.  While they were in this situation, my profession requiring it, I frequently went down among them, till at length their apartments became so extremely hot, as to be only sufferable for a very short time.  But the excessive heat was not the only thing that rendered their situation intolerable. The deck, that is the floor of their rooms, was so covered with the blood and mucus which proceeded from them in consequence of the flux that it resembled a slaughter house.  It is not in the power of human imagination, to picture to itself a situation more dreadful or disgusting.  Numbers of the slaves having fainted, they were carried upon deck, where several of them died, and the rest were, with great difficulty, restored.  It had nearly proved fatal to me also.  The climate was too warm to admit the wearing of any clothing but a shirt, and that I had pulled off before I went down; notwithstanding which, by only continuing among them for about a quarter of an hour, I was so overcome with the heat, stench, and foul air, that I had nearly fainted; and it was not without assistance, that I could get upon deck.  The consequence was, that I soon after fell sick of the same disorder, from which I did not recover for several months.

A circumstance of this kind, sometimes repeatedly happens in the course of a voyage; and often to a greater degree than what has just been described; particularly when the slaves are much crowded which was not the case at that time, the ship having more than a hundred short of the numbers she was to have taken.
This devastation, great as it was, some few years ago was greatly exceeded on board a Liverpool ship.  I shall particularize the circumstances of it, as a more glaring instance of the insatiable thirst for gain, or of less attention to the lives and happiness even of that despised and oppressed race of mortals, the sable inhabitants of Africa, perhaps was never exceeded; though indeed several similar instances have been known.

This ship, though a much smaller ship than that in which the event I just mentioned happened, took on board at Bonny, at least six hundred negroes; but according to the information of the black traders, from whom I received the intelligence immediately after the ship sailed, they amounted to near seven hundred.  By purchasing so great a number, the slaves were so crowded, that they were even obliged to lie upon one another.  This occasioned such a mortality among them, that without meeting with unusual bad weather or having a longer voyage than common, nearly half of them died before the ship arrived in the West-Indies.