"This Officer served as Headquarters Subaltern in the 4th Field Company S.A.E.C. throughout the period February 1941 to April 1942 with distinction. On the 10th November 1941 he assisted in carrying out a dangerous investigation of a New Type of Electronically controlled Time Mine placed by the enemy in the main Supply Railway Line which resulted in rendering of a report of great value. During the Battles for BARDIA and SOLUM Lieut. Blackwell took part in all the Company's activities and did sterling work particularly in the clearing and laying of Mine Fields under enemy fire and on two occasions under enemy observation.
He also did excellent work in improvising explosive missiles and Booby traps.
During the operations in and around TOBRUK area in April and May and June 1942 this Officer was employed on the staff of C.R.E. 2 S.A. Division where he carried out extensive Mining, and Defensive Operations in the areas of Fort Acroma, KNIGHTSBRIDGE, the CAULDRON and TOBRUK."