This page has been validated.
348
HIGH MAGNIFICATION CRESCOGRAPH
clockwork C (fig. 109). Successive dots are produced at definite intervals which could be made to vary from 1 to 10 seconds.
Fig. 109. The High Magnification Crescograph.
P, plant; C, clockwork for periodic oscillation of recording smoked glass plate G; S S′, micrometer screws; K, crank; R, eccentric; W, rotating wheel.
Two different methods are employed for obtaining the record. In the first, the records are taken on a stationary plate, the first series under normal condition, and the second under a given variation. The increase or diminution of intervals between successive dots in the two series, demonstrates the stimulating or depressing nature of the changed condition,
