Some new apparatus. 107 Pistol hey. This serves for investigating the reaction-time in starting to run. The blast from the pistol barrel a, fig. 21, moves the fan /so that contact is broken at d for an in¬ stant, the lever being drawn back by a spring. Only a few experi¬ ments have been made with the apparatus. These, however, have brought to notice the following facts : 1. the reaction-time is about one-third shorter for short- distance runners, who are trained Fig. 31. to start quickly, than for long-distance runners ; 2. the reaction¬ time for movements of the whole body is longer than for move¬ ments of a single member. Voice hey. The voice key, fig. 22, is in¬ tended for experiments on the time of associating ideas. It comprises a cylinder of hard rubber holding a metal plate at the end furthest from the mouth. A fine screw rests lightly against this plate. The current is sent through the point of contact between screw and plate ; it is interrupted by the vibration of the plate in response to the voice. With the spark method this pro¬ duces a chain of dots on the drum while the word is being spoken. Fig. 22, With two voice-keys and a telephone connection the person experimented upon can be in a distant room, a key being placed over the opening in each transmitter. Touch hey. A long flexible spring, fig. 23, is mounted in a wooden handle and bears against a short rigid arm, also attached to the handle, so as to keep closed än electrical circuit. The circuit is led into the handle