In the following weeks there were other attacks, and Frank (16th September 1916) tells us about a great British advance, and the capture of several villages; also of 'a new type of armoured car' with caterpillar tracks.  This was the first appearance on the battlefield of a new weapon, now universally known as the Tank. 
The Tank had been developed and transported to the war in great secrecy, and caused great consternation in the enemy ranks.  Often arriving in front of their positions in a smoke screen, causing initial panic and cries of 'Der Teufel kommt!' (the Devil is coming).  At this stage it was a weapon of unknown effect, so was not used in strength.