This is an image from a bound selection of the Canadian Government's official photographic series from World War I. The collection of 1772 images, representing around a third of all the official photographs known to exist in the series, was deposited at the British Museum in 1919/20 as part of the official copyright deposit collection. Individual photographs are not labelled, and no index has survived, but in many cases a number of the form "O.123" can be seen in the corner. This appears to represent an official numbering sequence. Some prints have been cropped and so the number is no longer visible; however, they appear to be bound in sequence. The volumes are numbered 1-4, and each page is recorded as "f001r", "f002r", etc.