Enquiry into the effects of loud sounds upon the hearing of boilermakers and others who work amid noisy surroundings / by Thomas Barr.

  • Barr, Thomas, 1846-1916
Date:
[1886]
Catalogue details

Licence: Public Domain Mark

Credit: Enquiry into the effects of loud sounds upon the hearing of boilermakers and others who work amid noisy surroundings / by Thomas Barr. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    person's hearing as it is that of the normal subject. He is, so to speak, profiting by the loudness of the voice while he is not dis- turbed or distracted by the din around him. While I was travelling lately along with a friend afflicted with deafness, in a steamboat on the Clyde, my friend remarked that he rejoiced when the steamboat whistle brayed forth, because then the speaker raised his voice and his deafness was hardly detected. Nevertheless, it is unquestionable that, apart from these modi- fying influences, the hearing, in the case of some deaf persons, is actually improved in the presence of loud noises. The explan- ation, probably, is that in such cases the three small bones of the ear have become stiff and rigid, and have lost their wonder- fully delicate powers of vibration in response to waves of sound, of moderate intensity, striking upon the tympanic membrane. When, however, they are shaken by strong coarse vibrations entering the ears, they are thereby, it may be conceived, rendered fit for the time being for transmitting ordinary vibrations from the human voice. In regard to the men under examination, with a few exceptions, they reported that they heard better in quietness. On questioning carefully the few who asserted that they heard better in a noise I was satisfied that the peculiarity could be explained by the circumstances already mentioned, especially by the loudness of the voice, and the proximity of the speaker. If the explanation just offered of the cause of hearing better in a noise is a correct one, the absence of this phenomenon noticed in these men still further corroborates the view that the nerve structures are the .seat of the lesion. 4. Noises in the Ears.—This is a very common symptom in the various diseases of the ear, in many of which indeed it is the main feature, and in a small number the only synqjtom for which relief is sought. I have been surprised at its comparative infrequency in these men. Only 8 men seemed to suffer permanently from these noises, and even in these the sensations were not of a distressing character. Thirty-four men, however, mentioned that they had at times noises in the ears; they were experienced chiefly after getting home at night, but were gone in the morning, or they were only present when they suffered from a cold. For a time after joining the trade, most apprentices are troubled with a sounding in the ears every evening for a few hours after leaving work. This comparative absence of persistent noises in the ears
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