Defective conditions of the vocal organs studied, in connection with questions of the oral method of training the deaf : the tongue / by Harrison Allen.

  • Harrison Allen
Date:
[1892]
Catalogue details

Licence: Public Domain Mark

Credit: Defective conditions of the vocal organs studied, in connection with questions of the oral method of training the deaf : the tongue / by Harrison Allen. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    pairs, that none are supplied as definitely to those which are toward the centre and are not in pairs. The distinctions-between the right and the left sides of the tongue are certainly greater toward the base than at the middle or the tip of the organ. The U-shaped or V-shaped median depression which is conspicuous in the mechanism of some of the vowels may be referred to in evidence of this symmetrical disposition of the dorsum. The convexities on the sides of the dorsum answer to the right and left values, while the median depression corresponds to the neutral territory between. But the front part is not so grooved in any lingual act. The tip and the region directly back of it never act as rights and lefts but always as a unit, hence no groove or other depressed interval is seen on this part of the dorsum. If I am correct in making these statements, is it not likely that articulation teachers may have an entirely distinct group of errors in the mechanism of speech, in which the basal part of the tongue enters, as contrasted with those in which the tip and associated regions enter ? From the statements just made the terms base and tip of the tongue are not exact, for the part at which the disposition for the groove to be well defined and where it ends is not sharply limited. It is certainly desirable that terms should bear a relation to use and that organs should be studied when practicable in connection with the work that is done by them. The terms base of the tongue and tip of the tongue leave the intermediate surface of the dorsum a terra incognita. I will venture upon this ground and attempt to outline it. I assume that between the base and tip are two regions which I name the pre-base and the post-tip. So that there are four regions o the dorsum. The tip is the hem which unites the two boi ders. It extends from the anterior end of the tongue a short distance only back- ward. post-tip, which extends from the tip for about an inch, and is usually distinguished by a median linear depression when the tongue is at rest. The pre-base lies, of course, in advance of the base and ranges from the circumvallate papillae to the end of the linear groove of the post-tip. It is often furnished in the centre by an oval clump of coarse papiUjE, as is here shown. (The figure of the tongue from Sappey's Anatomy was here referred to.) The base lies between the circumvallate papilhe and the frenum, between the tongue and the epiglottis.
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