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The passing of the tuning fork as an instrument of precision in measurements of auditory acuity has been brought about by the recent advances in electrical equipment, particularly in the development of the telephone receiver. With an oscillating electric current and a reliable control of this current in the telephone receiver, accuracy and flexibility not to be secured with the tuning forks have been made possible.Methods for testing the acuity of hearing for diagnostic purposes have developed along two rather widely diverging paths. From one group of examiners we hear the statement that hearing values for a few tones only are necessary. Opposed to these is another group, who insist that values for the tones of the entire audible range are essential for differential diagnosis. The factors determining the method in each individual case are the training and experience of the examiner, the ease of application of the

Audiometer curves, fields of hearing, audiograms and other types of charts illustrating in empirical or absolute values the power of hearing, are being discussed more and more frequently in the current journals. Interest in these records is by no means confined to the physiologist and psychologist who are interested in the solution of the problem of "how we hear," but physicists and engineers, railroads, the air service and other types of corporations are forced by necessity to take cognizance of such measurements in making adjustments for their special services. However, the greatest interest in these records and the keenest scrutiny of their context is undoubtedly being shown by otologists. In France, England, Italy and Germany we note that the members of this profession are becoming more interested, not only from the point of view of determining the effects of operative procedure or treatment, but more especially from that of diagnosis.

The consideration of this subject necessitates answers to two questions: 1. Is it generally recognized that hearing losses result from certain industrial hazards? 2. Can anything be done and is anything being done to prevent them?The first of these must be answered in a qualified negative. Some hazards to hearing are recognized and preventive measures, either direct or indirect, are being taken to eliminate them. Other hazards, because of the peculiar type of hearing loss which they cause, are not being recognized and no concerted action toward conservation has been taken.Recently an employer was asked what his reaction would be if some one asked permission to test the hearing of his employees. He replied that he preferred to let sleeping dogs lie. A locomotive engineer was asked if he would invite some members of his union to come to the laboratory for hearing tests. No charge was to

The causes of the variations in auditory acuity that are seen in the results of routine audiometric tests of hospital patients with "normal" hearing have been studied from the point of view of age1 as well as from that of the effects of certain systemic conditions.2 The purpose of the present study is to analyze the differences shown in the results secured by tests of males and females and of white and colored patients.The records analyzed are, as in the previous studies, secured from tests of patients in the medical and surgical departments of the Johns Hopkins Hospital. All tests were made with the same 1A Western Electric audiometer. The testing was done in the wards or in a small room set apart for that purpose. Neither was ideal for testing hearing, as neither was free from the disturbing effects of accessory noises, but the two

In an earlier paper1 is presented a statistical study of the records secured by testing the auditory acuity of 353 patients from the medical and surgical departments of the Johns Hopkins Hospital. The results of the study indicate that if the averages of the thresholds are computed, there is a distinct loss of acuity in each successive decade for tones above 512 double vibrations, but the averages of the thresholds for tones of lower pitch are fairly constant for all patients regardless of age. The statement was made that "it is hoped that the information thus secured will make possible the statistical analysis of the auditory defects associated with cerebral arteriosclerosis, hypertension, hypotension, syphilis, nephritis, disturbances of the ductless glands, the various diseases of the blood, lesions of the central nervous system and other conditions."In this paper the age variations in auditory acuity in a group of 468

For several years an attempt has been made at the Otological Laboratory of the Johns Hopkins University to correlate losses in hearing and defects shown histologically in the conductive and perceptive mechanisms of the organ of hearing. In carrying out this program, about 4,000 records of hearing tests have been secured, and serial sections of several hundred temporal bones have been made.The staff of the medical and surgical departments of the Johns Hopkins Hospital and of the medical department of the Bay View division of the City Hospital have cooperated in permitting an examination of the auditory and vestibular function on their patients and securing permission for necropsy. A large percentage of the patients tested recover and leave the hospitals, but the results of the hearing tests and the hospital histories are available for study along other lines.Accurate and complete hearing tests are necessary if