Page:Collected Physical Papers.djvu/316

296 undergoes an increase. The records given (fig. 79) are for amplitudes of vibration increasing from 5° to 40°, and decreasing from 40° to 5°. The successive stimuli are imparted at intervals of 1 minute. It will be noticed how the responses become enhanced under increasing stimulations.

Table I.—Showing the Increasing Electromotive Response under Increasing Amplitude of Vibration

It will also be noticed that whereas recovery is complete in 1 minute when the vibration amplitude is small, it is not quite complete within that time, when the vibration amplitude is large. Greater strain prolongs the period of recovery. Owing to want of complete recovery, the base line is tilted slightly upwards. This slight displacement does not materially affect the results, provided the shifting is slight. From other records taken through a greater range of stimulation, it appears that in a curve obtained with responsive electromotive variations as ordinates and amplitudes of vibrations as abscissæ, the first part of the curve is, generally speaking, slightly convex to the abscissa. This convexity