"We're not talking slave ship conditions here." For a fairly good (if slightly embroidered) description of conditions on board such a ship, prepared from his own experience of sailing on a smaller, better ship than that portrayed, see Herman Melville's "Redburn".

As to "Slave ship conditions" it is a fact that the emigrant trade began to expand almost coincidentally with the cessation of the slave trade. One wonders, to what occupation did the ships and crews that had been engaged in the slave trade turn?