The Chief Constable of Ramsgate (Mr. S. F. Butlen and the Chief Constable of Margate (Mr. C. J. Haycock) were among who witnessed tests of a spiked-mat device for trapping motor-car bandits carried out at the testing ground the London General Omnibus Company, at Chiswick. At the present time the only method of catching these bandits is to place across the road a barrier of policemen, who must give way or be run down. The new device consists of collapsible spiked mats.