Margaret Watkins moved to Glasgow - the city her parents had left to emigrate to Canada - in 1928. She never returned to North America, and more or less vanished. Not long before her death she gave her archive, wrapped in brown paper, to a neighbour who was interested in black and white photography and he had to promise not to open it until after she had died. The story of how, in the early 1970s, he discovered "one of the finest collections of artistic work achieved by the camera in the interwar era" is told here, Her last series of photographs was of Glasgow's building sites, and the Finnieston Crane (above, early 1930s) in particular.