I wrote this article for the 2018 edition of the Chapka, the Regimental Journal of The Royal Lancers (the Chapka was the distinctive helmet adopted by British lancers in the late 19th century). The Royal Lancers incorporates the 9th (Queen’s Royal) Lancers, the regiment of my grandfather Tom Verrinder and his brother Edgar during the First World War, and this article is based on their experiences on 15 September 1916 during the Battle of the Somme - the day that tanks were first used in action. A comprehensive account of my grandfather’s experiences with the 9th Lancers during the war forms the basis of a book currently in preparation.