The first modern tank. Colonel (later General) Estienne, foresaw that the solution to the stalemate of trench warfare could lie in the use of tracked armoured vehicles. Finally permission was granted to develop such a machine. After two models that were not successful Estienne worked on a design with Louis Renault, the motor manufacturer. It was to prove one of the most successful tanks of the First World War and played an important part in the affairs of other armies as well as that of France. It was a light, two-man machine designed to act as an armoured skirmisher. The Renault proved invaluable and was employed with distinction when the Germans went over to the offensive in 1918. The tracks were sprung and ground pressure was reduced to seven pounds per square in inch, the optimum for light tanks. A tail skid at the rear overcame any tendency to overturn when negotiating the side of a deep trench. With a speed of nearly 6 mph and only 4 m (13 ft) long, it could cross a 2 m (6 ft 6 in) ditch. Although ready by April 1917 squabbles and delays held up production for a year. A total of 3,800 were constructed before the end of the war. The Renault made its battlefield debut on 31st May 1918 The hastily formed tank battalions were rushed forward to help stem the tide of the German offensive. By the 18th July some four hundred were concentrated for a counter-attack near Soissons where, with the medium tanks. they quickly broke through the German line. After the war, many of these tanks were sold to foreign governments including Italy and Russia. This tank can be seen today at The Tank Museum, Bovington, Dorset, UK.