This book is by turns detailed, incoherent, and frustratingly colonialist. Nevertheless, it is written by an intelligent and sympathetic European observer who spent many years studying West African folklore, culture, and religion at the turn of the 19th century. It is useful because it goes into much greater detail than any other book from this period about Bantu and Yoruba spiritual practices and philosophy. The problem is that it presents some very half-baked theories as to the significance of this data, which should be treated with great caution.
By reading this book critically we can glimpse a system of nature worship, sacred kingship, and shamanism from before the colonial era, and get a hint of a very complex philosophy of esoteric corespondences which rival the better documented systems (e.g. the Upanishads, the I Ching and the Qabalah). - JBH.