I've recently discovered a family group photograph taken c. 1916 which shows my great-uncle in his khaki army uniform. Only his head and shoulders are visible but this is enough to show that he is wearing what looks like a piece of white cord around his right shoulder which seems to be placed underneath his epaulette and loops under his arm. Unfortunately, I haven't yet discovered details of his regiment and rank. I would be very grateful to anyone who could let me know what the white cord may signify. Many thanks.