Frederick F. Geach
Mining engineer. Worked for the Portuguese government in Timor, where he met Alfred Russel Wallace in 1861, and was working in Malacca (Melaka) in 1867. Later a mineral and consulting engineer in Guildford, Surrey.
BMD (Death index)
Census returns of England and Wales 1871 (The National Archives: Public Record Office RG10/812/45/34)
Correspondence vol. 15, letter from A. R. Wallace, 2 March 
England & Wales, national probate calendar (index of wills and administrations), 1858–1966 (Ancestry.com, accessed 21 August 2015)
Marchant ed. 1916