A detailed study has been made of the scratches produced by a needle on natural rubber vulcanizates of different composition. The surface damage brought about in this way depends markedly on the nature of the rubber. In particular, the traces on unloaded vulcanizates are discontinuous whereas the traces on carbon loaded rubbers of the tire tread type are continuous. It has been found possible to explain the results qualitatively by reference to hardness, friction, and tear resistance of the vulcanizates.