For extraordinary heroism in battle, engagements of Vera Cruz, 21-22 April 1914. Posted on the roof of the Terminal Hotel and landing, Ens. McDonnell established a signal station there day and night, maintaining communication between troops and ships. At this exposed post he was continually under fire. One man was killed and three wounded at his side during the two days’ fighting. He showed extraordinary heroism and striking courage and maintained his station in the highest degree of efficiency. All signals got through, largely due to his heroic devotion to duty.