Page:Collected Physical Papers.djvu/368

348 clockwork C (fig. 109). Successive dots are produced at definite intervals which could be made to vary from 1 to 10 seconds.

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,