Page:Collected Physical Papers.djvu/266

246 moderate and uniform sensitivity. All these phases are well seen in fig. 56 where (a) exhibits the preliminary stages, and (b) the steadier condition, with more uniform response. The up-curves show the increase of current under the flash of radiation, and the falling and concave portions, the recovery on the cessation of radiation. In self-recovering receivers of the negative type the response curves are the reverse of these, in the sense of the reflected image in a mirror.

The Characteristic Curve of the Self-recovering Receiver of Positive Type

I now subjected the self-recovering receiver to a continuously increasing electromotive variation, and