Rank: Lieutenant Colonel
This Boer-War Soldier record for RH BUCHANAN-RIDDELL was transcribed record from various documents held at the National Archives, South Africa. Data contained in this set is known as "The Soldiers of the Queen".
https://www.gendatabase.com/boer-war-soldiers-record.php?q=11848&r=RH&s=BUCHANAN-RIDDELL&ref=
