steady and permanent condition, when the responses are uniform: and lastly (5) when vibration is continued for too long a time, the positive tends to become less positive, the responses decline— state of things which we designate as fatigue.
Increased Electromotive Variation with increased Intensity of Stimulus.
When the intensity of stimulus is increased by increasing the amplitude of vibration, the electric response is enhanced. The following is a pair of records (fig. 9) for increasing amplitudes from 5° to 40°, and decreasing amplitudes from 40° to 5°. The vibrations are imparted at intervals of 1 minute. It will be noticed how the response is enhanced with increasing stimulus.
Fig. 9.—Photographic records of response curves. (a) from 5° to 40°, (b) from 40° to 5°. The vertical line = 0.1 volt.
Table I.—Showing the Increasing Electromotive Effect due to Increasing Amplitude of Vibration.
| Vibration, amplitude. |
Deflection. 23 dns. = 0.1 volt. | |||
| 5° 10 20 25 30 35 40 |
Ascending. 5.5 13 25.5 33 39 43 47 |
Descending. 5 12 26 32 39 43 48 |
||
