'At Messines on 7th June 1917. During the operation on the Messines Ridge this man was a member of the Forward Observation Officer's party. They laid, and for hours endeavoured to maintain communications under very heavy shell fire. For a period of twenty four hours they were continually working on the wire, repairing breaks until communication was finally established. On the 9th June, volunteers for a similar task were called for, this man volunteered and was again included. When one of the party was wounded Gunner McDonald, assisted by three others, carried him under heavy fire to a dressing station. His coolness and gallant conduct during the whole period was a splendid example to the other men.'
Source: London Gazette
Date: 16 August 1917