I STRONGLY feel that the exact determination of the hearing function should be the otologist's concern and have found that the principle of the percentage scale of hearing in the tuning-fork test hitherto used was illogical from the standpoint of acoustics. Through my experiment I arrived at the conclusion that the usual tuning-fork test should be abandoned for a modified one to which the principle of time difference was applied. What I term the principle of time difference is found by multiplying the damping constant of a tuning fork by the time difference between the hearing period of a deaf person and that of a normal person for the same tuning fork. This matter has already been described by Harvey Fletcher1 in his book, "Speech and Hearing."
From this principle I have derived a convenient method of measuring the damping constant of a tuning fork, as well as an