chronoscope

The clock used for exact work is likely to be the Hipp chronoscope, which gives on its dials indications of time intervals in thousandths of a second.

As soon as the point touched the animal the chronoscope circuit was broken by the raising of the upper arm of the key.

Besides, I had read articles about the chronoscope, the plethysmograph, the sphygmograph, and others of the new psychological instruments.

IC, interrupted circuits; CC, chronoscope circuit; X, key for making stimulus circuit and breaking chronoscope circuit; B, stimulus battery; S, string from reaction key to animal.

The stimulus key, X, was a simple device by which the chronoscope circuit, c, c, was broken at the instant the stimulus circuit, s, c, was made.