Drum of Power — Bill Knox

Robert Hartford's search for a sisal-growing area in the former British colony of Yabanza suddenly turned into a desperate expedition, endangering the lives of his small party of Africans and Europeans. Hartford's real task was to destroy the Drum of Ungara - an ivory relic of Africa's past, with the power to turn the forthcoming elections into a defeat for the government party. A dead native, a handful of Maria Theresa dollars, a half-caste mercenary and a hospital sister all had their parts to play before the drum's destiny was fulfilled.