Server connection off-line just now but this will help later.
Service records of the South African Constabulary are called Records of Conduct and Service and are held at the National Archives of South Africa in Pretoria and Bloemfontein. You can use the NAAIRS system of the SA National Archives and Records Service at
http://www.national.archives.gov.za/index.htm to search for records, from the home page LH side menu 5th item down “search etc” then select either a repository code or RSA if you don’t know the repository. Enter line 1 surname, line 2 record of conduct; dates 1900-1910.
If he did serve in the South African Constabulary in SA, I’m sure you’ll find Baden-Powell’s Proclamation of interest, see
http://www.angloboerwar.com/forum/13-miscellany/1235-south-a...