One theory is that 'if the linear distances vary between the individual characteristics found on an inked print and a latent print, or between the individual characteristics found on two inked prints, it must be concluded that the two examples of friction skin were not made by the same person.' To test this theory, the left thumb print, a double loop pattern, of a 28-year-old male was recorded 16 times. The thumbprints were visualized using black ink on a white card. Varying amounts of pressure and rotation were purposely used during print deposition. Measurements were made using a divider, and they were read to the nearest millimeter on a rule. The second theory is that 'if the number of ridges per unit of measurement varies in the comparison of an inked print and a latent print or between two inked prints, it must be concluded that the two examples of friction skin were not made by the same person.' To test this theory, the hypothenar area of the left palm of the same subject was recorded seven times, and measurements were made as in the first test. Neither theory was supported by the data. Linear distances varied, and the number of ridges per unit of measure varied. These experiments were repeated with other persons with similar results. 5 tables, 8 references.