The Dogs of the First World War exhibition at the Bishopsgate Institute in London explores the role of dogs as both companions and workers during the years 1914-18. It features photographs from Libby Hall, who for more than 40 years collected old pictures of canines that show their unique bond with man.
These messenger dogs were photographed by Lt Col E H Richardson learning to work amid rifle fire.
Picture: Libby Hall Collection, Bishopsgate Institute Archive