The general results of the first series of experiments with this apparatus were similar to those already given, but were based on a very much larger number of judgments. They show at once that the short filled spaces are overestimated, while the longer spaces are underestimated. The uniformity of this law has seemed to me one of the most significant results of this entire investigation. In the results already reported from the experiments with the former apparatus, I have mentioned the fact that the judgments upon the distances fluctuate more widely when one is filled and the other open, than when both are open. This fluctuation appeared again in a pronounced way in the present experiments. I now set about to discover the cause of this variation, which was so evidently outside of the limits of Weber's law. TABLE XI. I. II. Subjects. R. B. A. R. B. A. 2= 3.1 3.2 3.7 2.7 2.5 3.1 3= 4.5 4.4 4.1 4.1 4.0 3.6 4= 5.3 5.0 4.3 4.2 4.6 4.6 5= 6.0 5.1 5.8 5.9 5.2 4.3 6= 6.8 5.6 6.2 6.9 5.3 6.0 7= 7.4 7.2 6.9 7.6 7.3 6.8 8= 8.1 8.4 7.3 8.3 9.7 7.8 9= 9.3 9.0 8.5 9.5 8.9 8.7 Filled 10= 10.1 10.0 8.1 10.3 10.0 9.2 Spaces. 11= 10.5 9.3 9.7 10.6 8.7 9.6 12= 11.7 10.6 10.6 11.8 9.7 10.2 13= 12.3 10.9 10.9 11.1 10.2 9.6 14= 12.2 11.5 12.2 10.4 9.6 11.3 15= 13.6 12.3 11.9 13.1 10.1 9.6 16= 14.1 13.5 14.1 12.3 13.2 13.3 17= 14.9 12.9 14.6 14.1 12.6 13.7 18= 15.0 15.3 14.9 15.0 15.3 13.8 19= 15.2 14.6 15.2 14.1 13.9 14.2 20= 17.1 16.5 15.7 16.1 16.4 14.7 The first line of group I. reads: 'When the finger-tip was passed over a filled space of 2 cm., the subject _R_ measured off 3.1 cm. on the open space, the subject _B_ 3.2 cm., and the subject _A_ 3.7.' In group II., the numbers represent the distance measured off when both spaces were unfilled.