On the outskirts of London, in a basement room of the British National Archives, a historian delicately turns pages that have the brittle feel of dead leaves. Each is covered in text — some typewritten, some in spidery handwriting from a pen that scratched across the page 100 years ago.
"Saturday, the 26th of September, 1914," reads one. "The most ghastly day of my life. And yet one of my proudest, because my regiment did its job and held on against heavy odds."