Page:Eleanor Gamble - The Applicability of Weber's Law to Smell.pdf/55

Rh the propensity of the movable cylinder of the small instrument for slipping are quite enough to explain the fact. The mean variations of Rob., Rog., Se. and Sk. closely resembled those of T. both in size ond in degree of uniformity. Those of Be., Bi., C., M. and N. ran higher, and were more irregular, This fact was undoubtedly due to hasty movements in the cases of Bi., C., and M., and to exhaustion in the cases of Be. and N. D.'s mean variations were large and irregnlar in the beginning but improved with his manner of moving the cylinder and K.s also were large at first, but finally approximated to T.s. P.'s were suspiciously small, as small with the fluid-mantle as with the standard olfactometer, and indicated the movement-error beyond a doubt.

Results connected by W. (“with”) were found on the same day for the same nostril. The values obtained with gray rubber were chosen for illustration because vulcanized rubber was used with three different methods, and those obtained with coumarine were taken because this scent was used with all the thirteen subjects. Both sets are fair samples of the whole mass of results, The series of Be. and D. with gray rubber, and of Bi., C., K., M., N., Rob. and Sh. with coumarine, give pretty clear indications of the validity of Weber's law. That of Se. with rubber, and those of D., P., Rog. and Sh. with coumarine, indicate the operation of the lay simply by the fact that as a rule the numerators of the fractions with the larger denominators are larger. The series of Be. and T. with coumarine are too short to prove anything by themselves. A series in which the numerators of the fractions with the larger denominators are persistently smaller than those of the fractions with the smaller denominators or equal to them may be counted as tending to disprove the law.

In the complete set of results—counting the results of one subject with one substance as ope series—there are 55 series for solids. Out of these, 15 indicate Weber's law clearly ; 14 indicate it faintly ; 11 long

IIV.

Approximate Values of $Δr/r$ obtained for Pairs of Standard Stimulus-Intensities Sensed under the Same Conditions,—viz: Subject, Nostril, Substance, and Hour.