He saved at least 300 people at the cost of his own life. His final message is very moving.

'Coleman remembered that an incoming passenger train from Saint John, New Brunswick, was due to arrive at the railyard within minutes. He returned to his post alone and continued to send out urgent telegraph messages to stop the train. Several variations of the message have been reported, among them this from the Maritime Museum of the Atlantic:

"Hold up the train. Ammunition ship afire in harbor making for Pier 6 and will explode. Guess this will be my last message. Good-bye boys." Coleman's message was responsible for bringing all incoming trains around Halifax to a halt. It was heard by other stations all along the Intercolonial Railway, helping railway officials to respond immediately.[71][72]

Passenger Train No. 10, the overnight train from Saint John, is believed to have heeded the warning and stopped a safe distance from the blast at Rockingham, saving the lives of about 300 railway passengers. Coleman was killed at his post.'