African Memoranda: Relative to an Attempt to Establish a British Settlement on the Island of Bulama, on the Western Coast of Africa, in the Year 1792. With a Brief Notice of the Neighbouring Tribes, Soil, Productions, &c. and Some Observations on the Facility of Colonizing that Part of Africa, with a View to Cultivation; and the Introduction of Letters and Religion to Its Inhabitants: But More Particularly as the Means of Gradually Abolishing African Slavery