The Northwestern University, Chicago has recently made a large collection of historical photographs available online at website http://repository.library.northwestern.edu/winterton/
The Humphrey Winterton Collection of East African Photographs: 1860 – 1960 includes over 7,000 photographs from numerous sources, depicting life in Africa from 1860 – 1960. They include photographs of Zanzibaris and other Africans as well as the travels of European explorers, traders, colonialists and soldiers.
Group of British sailors posing in front of the Beit al-Ajaib - Bombardment of Zanzibar 1896 - Winterton Collection of East African Photographs: 58-5-2
Dar-es-Salaam, (German East Africa) Kaiser St. & harbour. Aug. 23rd 1986 - Winterton Collection of East African Photographs: 12-1
Machine gun in action, Bugaro, East Africa Campaign. Circa 1914-1918 - Winterton Collection of East African Photographs: 8-6-3
Sultan's Palace, Zanzibar with a crowd in the foreground circa 1893 - Winterton Collection of East African Photographs: 64-12
The Sultan being shown round a European-owned factory circa 1920-1930 - Winterton Collection of East African Photographs: 68-2
Sultan and other Zanzibari officials walking past cannon, Zanzibar 1905 - Winterton Collection of East African Photographs: 72-3-38