SOLVED. British Geologist goes missing in Africa whilst on a surveying job. He inadvertently uncovers a plot by the bad guys who try to kill him. He ends up on an Island in Lake Vic.,with brain injury. Sister back in England tries to find him. [s]

[Bruce]

This book was an old audio book (8 audio casettes) that i borrowed from my local library in 1997....no record remains.
The book starts with Arab slavers in 1700s. slaves are loaded onto a Dhow which sinks in Lake Victoria?? during a storm. There is an island where tribal ceremonies make victims jump into a lagoon where they are devoured by large crocodiles. Island is later colonised by monks who build a Monistary - the ruins of which feature prominently in the latter part of the story
Story line then moves to geological exploration in Africa post WW II where the geologist vanishes. Sister back in England organises search party and gets into all sorts of trouble. Geologist is eventually found living on the island with villagers. He has brain damage from earlier escapades with the bad guys and helps provide income to the village by carving ivory figures and trinkets. Sunken treasure is found on an old wreck in the lake

[Lobstergirl, au gratin]

Bruce, your headline is a good start but you will get more clicks if you add plot details to it.

[Bruce]

BUMP

[Kris]

The Medusa Stone by Jack Du Brul?

[Bruce]

Have finally managed to find this book!!! For those interested is Beverly Harper. "Echoes of an angry god". Can't wait to read it again. Thanks to all those who read this thread.

[Kris]

Glad you found your book! Echo of an Angry God by Beverley Harper for the link.