101

G103

plated by the investigator and compared with the next intenser in the series, the interval of intensity between them shall appear to the contemplator's feeling [to] be equal to the interval between any other one of the series and the member next intenser than it. It is certain that this can be done, since all sidereal astronomers since Ptolemy have practised this; and many psychologists beside me have done something similar for other feelings than that of luminosity. It has been demonstrated that a series of positive numbers integer and fractional expresses in itself nothing more than an order of succession. But this scale is made to express besides a feeling of a difference of feeling in one respect; and