But what about land artillery?

In the same war, trench warfare had led to a stalemate along the western front. The emphasis was on sieges rather than on manoeuvring and formations. Vehicles referred to as ‘land ships’ were being developed in the United Kingdom to achieve a breakthrough. To maintain secrecy, the workers of the company that built these vehicles were told that they were working on water-carriers for Mesopotamia, modern day Iraq.

This is the origin of the word ‘tank,’ for that is what the vehicle involved was. It was put together by the British, starting from an American tractor. They gave it caterpillar tracks, a feature they already used in gun tractors. They equipped it with weapons mounted in turrets and enclosed it in armour to protect it against bullets. The tank has been one of the best solutions to the problem an army faces of needing to advance even when under fire. The Assyrians once used movable barriers for their archers. The Romans used towers equipped with catapults. These were shielded structures that moved on wheels. Metal-plated wagons mounted on wheels were used in parts of Europe during the Middle Ages.