Standing proudly beside their friends and fellow soldiers, 46 men of the 8th Berkshire Regiment pose for a group photograph in May 1915.
The sun was shining, their training almost complete and many were keen to see action for the first time.
But within four months of this haunting picture at their training camp near Warminster, Wiltshire, they were fighting the Battle of Loos.
That one action left ten men dead and another seven wounded.
By the end of the war, 19 of the brother officers had been killed, nine seriously wounded and the group had been scattered.
None were left untouched by the horrors they shared — and some carried those secrets to their graves years later.
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