North - Smith Mackenzie & Co., Zanzibar; Appt. Acting US Consul Zanzibar 20/7/1891, resigned as Consul 31/1/1892; Smith Mackenzie's agent at Kampala April 1892; dep. Zanzibar for Madagascar 2/11/1895; dep. Zanzibar for Seychelles Feb 1896; at Mumias when Sudanese mutiny started & volunteered to help troops ept 1897; Luba's Oct/Nov 1897; East & Central Africa Medal, clasps 'Lubwa's & Uganda 97-8'; dep Kampala for coast 4/8/1898, arr. Mombasa 13/10/1898; at Zanzibar & due to dep for Boston soon 26/10/1898; awarded £200 by the FO for services rendered during Sudanese mutiny 1899; arr Zanzibar to take up management of Mombasa operation for Arnold Cheney & Co. 14/1/1904; at Mombasa 11/6/1904; resigned from Arnold Cheney & Co., going up-country July 1904; Bird Licence Entebbe 27/6/1905; resident at Mweli, firearm registered at Vanga 21/10/1905

Uganda Journal Vol 1 No 2 - Cook - The Journey to Uganda in 1896 - ……. At the Eldama Ravine we found Dr Macpherson, Vialle and Captain Bagnall. The latter provided us with an escort through the treacherous Kamasia country.

Web - 1907 Edward Vialle is appointed American Vice-Consul General in Ethiopia. 1908 - Vice-Consul General Vialle leaves  …

Newspaper reports in Ancestry say he won the VC for his Uganda service (when Thurston was killed) but he is not in the list of VC recipients in Wikipedia. But apparently he showed the VC to one of the newspaper's correspondents.