It was at the Battle of Flers-Courcelette on the Somme, in September 1916, that tanks first went into action ... people would think of something used for storing water rather than a war machine.

Horace Leslie Birks was put in charge of one of these early tanks at Passchendaele. HORACE LESLIE BIRKS: This was the first time I had ... This clip could be used as an introduction to an ...