remaining A7Vs in turn withdrew. As Lt. Mitchell's tank withdrew from action, seven Whippet medium tanks also engaged the infantry. Four of these were knocked out in the battle, one of the A7Vs destroyed one Whippet and damaged three ones (three more Whippets were destroyed by German artillery). Lt. Mitchell's tank lost a track towards the end of the battle from a mortar shell and was abandoned. The damaged A7V was later recovered by German forces. All 18 available A7Vs had been put into action that day with limited results; two toppled over into holes, some encountered engine or armament troubles. After a counterattack, three ended up in Allied hands. One was unusable and scrapped, one used for shell testing by the French, and the third captured by the Australians when the Infantry moved forward and dragged it back to their lines, the Germans still being in a position in sight of the tank and firing at them. The tank name,"Mephisto" of this captured A7V is painted on the end facing of the box-shaped tank chassis serial number 506, as almost all German tanks in WW1 were given individual names. The A7V was not considered a success and other designs were planned by Germany, however the end of the war meant none of the other tanks in development, or planned ones, would be finished (such as the Oberschlesien, K-Wagen, LK I or LK II). The final use in World War I of A7Vs was in October 1918; a number were scrapped before the war ended in November. The extremely limited production of twenty A7Vs made a very limited contribution, and most of the tanks (less than a hundred in total) that were fielded in action by Germany in World War I were captured British Mark IV tanks (Beutepanzer). The British tanks were repaired and overhauled in workshops established at Charleroi and rearmed with 57mm Maxim Nordenfelt guns in place of their 6-pounders. Some French tanks (including Renault FT light tanks) were also captured during the German offensive in November 1918, but no changes are known to have been done. Post World War I After the war, many nations needed to have tanks, but only a few had the industrial resources to design and build them. During and after World War I, Britain and France were the intellectual leaders in tank design, with other countries generally following and adopting their designs.