Mobile world in car will silicon London's tubes, push button control. In connection with London Transport's effort to make London's troops silent, the boards engineers have devised a new type of rail welding and grinding car. Controlled by pushbutton, the complete plant can world automatically in three minutes, the heaviest of rails. Photo shows, finishing of the weld joint with an electric milling machine, at the armaments way depot at Fulham 3 February 1938