This is a significant and very interesting map of western Africa from Cape Blanco and the Senegal River southwards past Sierra Leone, the Grain Coast, the Ivory Coast, the Gold Coast, the Waydah, Benin, Calabar, the Seven Hill, and Majumba, to Angola.  The inset in the upper right details in much greater detail the Gold Coast. Towns/settlements, rivers, roads, forrests, prevaling seasonal tradewinds, etc are shown.  This map is a reference for the African slave trade of the mid-18th century.  Many of the coastal cities along the coast are all slave ports. The document breaks down which country and company control each fort, occasionally providing a short history and context within the slave trade. For example with regard to Annemboc Fort, on the Gold Coast, Postlethwayte says