抄録
Five kinds of markers were employed in the experiment. All of them were 0.75 mm thick, but were different in radius. The depths of marks made on several pieces of the same kind of cotton cloth with the markers were measured by a special microscope. The following results were obtained :
1. The smaller the radius of curvature is, the deeper the streaks made by the marker are, but the depth of the streaks is not in reverse proportion to the radius of curvature.
2. As the streaks deepen, something like nodes developes in the streaks, and sometimes projections grow at the ends of the streaks ; consequently the depth of the streaks decrease suddenly.
