German botanist and colonial administrator Paul Erdmann Isert (ca. 1756 – 89) arrived in November 1783 at a time when the Danish forts at Ada, Keta, and at Teshi were being built on the Gold Coast. Isert stayed on the Gold Coast for three years, leaving in October 1786 by way of a slave ship bound eventually for Copenhagen. After two days at sea, the Gold Coast captives onboard revolted.