Three young British soldiers with faces that you might see in a pub today. They are wearing the “Gor Blimey” soft caps first issued in 1915. Their scuffed and chalky boots suggest that they have recently been in the front line. On each day until the centenary on 1 July, we are publishing a “Selfie from the Somme” – an image chosen from a collection of more than 700 long-lost photographs brought to light by The Independent in recent years.