I. The mean total time taken from 450 experiments on sixteen subjects was found to be 0.0420 second.
II. Natural winks occurring very shortly before the record was taken had no influence.
III. The reflex time was found to vary in different individuals, the limits of the mean times being 0.0351 and 0.0491 second. For any given individual there was a close correspondence between averages of sets of experiments obtained under similar conditions. In the case of one man this was true of sets of experiments taken a year apart. Sex has no influence.
IV. Apprehension seems to shorten the time.