Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Battle of Loos was one of the major British offensives mounted on the Western Front in 1915 during World War I. It marked the first time the British used poison gas during the war, and is also famous for the fact that it witnessed the first large-scale use of 'new' or Kitchener's Army units.The battle also marked the third use of specialist Royal Engineer tunnelling companies, who deployed mines underground to disrupt enemy defence lines through the use of tunnels and the detonation of large amounts of explosives at zero hour.