It has long been a clinically and experimentally well recognized fact that the hearing organs of man and animal would be impaired by the excessive sound stimuli. It has also been pointed out that the hearing organ of each man
is not always impaired in the same degree by the same noise, and their impairments show the individual variation in a considerable range. It is indeed not too difficult to imagine, that, under the same acoustic condition, such individual variation of the acoustic impairment owes to the inherent disposition of each man. But at the same time, this individual variation may more or less owe to the patency of the ear tube; the normal tube having a physiological function to control the unnecessary acoustic stimuli, and on the contrary, the stenosed tube being devoid of this function, induces more impairment of the hearing organ. This latter suggestion, which occured to the author, led him to attempt the following experiment.</p
