While in the UK in 2105 we went to the Imperial War Museum. I was looking forward to seeing some WWI tanks but there were very few there. However, I did pick up a little word history: tanks as armoured, gun-mounted vehicles moving on caterpillar tracks got their name as part of their top-secret development during WWI.

The earliest armoured vehicles in WWI were designed to clear away the barbed wire that restricted the movements of infantry on the battlefield. The prototype machines were built on tractor chassis and soon were using caterpillar tracks already being used in US farming. Caterpillar tracks provided significantly more grip on the churned up ground of the battlefields than wheels.

Benjamin Holt patented the first caterpillar design in the US. Holt replaced the wheels on one of the farm vehicles he manufactured with a set of wooden tracks bolted to chains after returning from England, where he had seen a demonstration of a prototype chain-track by Richard Hornsby & Sons. In 1904 he successfully tested his design with his photographer Charles Clements on hand. Clements suggested that the tractor crawled like a caterpillar and Holt liked the metaphor and used it for the name of the new traction system. Another story says that Holt picked up the name from British troops also watching the Hornsby prototype earlier.

In early 1915, Winston Churchill, then First Lord of the Admiralty, created the Landships Committee to develop armoured fighting machines for use in trench warfare (they were also called land warships). The project was kept secret because Churchill was concerned that the military establishment would block the project. However, when the War Office did find out about the project the Committee of Imperial Defence recommended the “caterpillar machine-gun destroyer” machines be managed by an entity “which, for secrecy, shall be called the ‘Tank Supply Committee’”. This was the first recorded use of the word tank for the landships.

The name, tank, was a subterfuge or codename to conceal the nature of the project. Cistern and reservoir were also considered as cover names to suggest the boxlike steel machines were water vessels. One story suggests that water container was rejected because the committee would have been known as the WC Committee (WC being a common British term for a toilet), but I am not sure it is true.

The committee came up with a tank design in late 1915 known as Little Willie—a derogatory nickname for the German Crown Prince. However, a more advanced design known as Big Willie, His Majesty’s Land Ship Centipede or Mother soon followed. These tanks were armoured, mobile, gun platforms designed to protect and support the infantry.

Tanks were first used at The Battle of Flers–Courcelette on the Somme on 15 September 1916. General Sir Douglas Haig wanted the tanks used but it was against the advice of nearly everyone: the tank engineers, his sub-commanders and the French. The military men thought the tanks still needed further development and many did not want the “secret weapon” revealed to the enemy until there was enough tanks to be decisive. The tanks did not perform well but did provide a massive boost to soldier morale while frightening the Germans.