Observations upon the Windward Coast of Africa, the religion, character, customs, &c. of the natives, with a system upon which they may be civilized and a knowledge attained of the interior of this extraordinary quarter of the globe and upon the natural and commercial resources of the country, made in the years 1805 and 1806; with an appendix containing a letter to Lord Howick on the most simple and effectual means of abolishing the slave trade.