List of sources:
Cape of Good Hope almanac and annual register, 1856, 1857.
Cape of Good Hope
Government Gazette, 9 January 1885, p. 44. List of chemists and druggists in the Cape
Colony.
Grahamstown Journal, 11 August 1855; 26 January 1856; 16 February 1856; and 25 November 1856: Literary, Scientific and Medical Society.
Grahamstown Literary, Scientific and Medical Society. Minute Book, 1855-1861 (Albany Museum, Grahamstown).
Kaapsche Grensblad, 17 November 1855, Landbouwkundig Genootschap.
National Automated Archival Information Retrieval
System (NAAIRS). http://www.national.archives.gov.za/naairs.htm
Documents relating to RM Armstrong.