Page:Philosophical Review Volume 1.djvu/597

No. 5] depth of his calculations. Thus he took ten minutes to perform the following five operations: 1st, addition of 22,423, 379,999, 823,111, 79,437; 2d, square of 940, and square of 953; 3d, division of 482,765 by 4760; 4th, cube root of 121,287,375; 5th, fifth root of 847,288,609,493. Of the ten minutes taken to perform the above, about five were devoted to repeating the numbers as they were given out. Good professional calculators could work out on paper and in about the same time all that Maudi did mentally; in fact, he simply used his extraordinary memory for figures where the common calculators used pen and paper. Whether his memory was auditory, neural, or motor was not determined: Maudi himself called it 'auditory,' but did not clearly understand what the term meant.

The odorous substances used were not complex natural 'essences,' but bodies which were chemically well defined. Expressing the threshold values in millionths of a gramme, P. found for camphor 5, for ether 1, for citral 0.5, for vanilla 0.005. The odoriferous power of an odor is to be distinguished from its intensity: the former is inversely as the threshold value; the latter is determined by the relative amount of a substance required to mask the odor of another. Thus, when threshold amounts of citral and vanilla are put together in a flask, the vanilla alone is perceived; but if the citral is increased tenfold in weight, the vanilla would have to be increased one hundred times to be perceptible. The intense substances correspond to Beaunis' odors [short reaction time]; and the powerful substances to Beaunis' perfumes [long reaction time]. The 'minimum perceptible' varies with different individuals, and with the same individual at different times.

Natural selection operates in morals and politics as well as in the vegetable and animal worlds, but with differences that have caused it to be misunderstood. In the former it is a struggle, not of lives, but of ideals. The reformer represents a plan of conduct that is a variation from the typical plan. A struggle ensues, the old unmodified plans of