Members of the Women's Royal Canadian Naval Service climb a signals mast during training at HMCS St. Hyacinthe, near Saint-Hyacinthe, Quebec.

In this photograph, Wrens, wearing naval trousers, pose on a ladder while colourful signal flags flap in the breeze. Flags like these, as well as semaphore flags waved by people, were still a vital means of communications. Unlike radio transmissions, they could not be picked up by a distant enemy, and did not give away a ship's location.

George Metcalf Archival Collection
CWM 19840030-044