Defective hearing : its curable forms and rational treatment / by James Keene.

  • Keene James, 1833-1883.
Date:
1876
Catalogue details

Licence: Public Domain Mark

Credit: Defective hearing : its curable forms and rational treatment / by James Keene. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    the M and the N. When these are deprived of the nasal expiration which should accompany their articulation, they become B and D re- spectively. This will be readily perceived by endeavouring to pronounce a word or mono- syllable containing a nasal consonant, while the nose is closed. Me will then become be, no do, moon dood, sun sud, and so forth. By placing a cold mirror below the aper- tures of the nostrils, in such a manner that its polished surface is directed upwards, and out of reach of the breath issuing from the mouth, we may readily satisfy ourselves that nasal expira- tion actually takes place during the pronun- ciation of syllables containing M and N, and with these only. In this manner we may repeat each of the consonants, in combination with each of the vowels, without any deposition of vapour taking place on the mirror, until the syllable contains m or n, which will at once become manifest by the appearance of a spot of dimness on the glass. If we take into consideration the relative positions assumed by the organs of articulation —the tongue, lips, teeth, and palate —we shall perceive that they are the same for the pro- nunciation of me and be, no and do, and conse- quently we may infer that the difference between the sounds produced depends upon B 2