Dr. Marshall Hall on Stammering. 259 



of compressed air, in the case of the letters F and V, between 

 the lips, in that of the T H, between the tongue and upper teeth, 

 and in that of the letters S and Z between the teeth. In the 

 stammering enunciation of the letters of the third class, there 

 is frequently a state of laborious respiration. In all these cases, 

 then, it is plain that the larynx is open ; any considerable effort 

 applied to the parts concerned in the articulation of the first 

 class of letters, the least noise, the least escape of air, alike 

 demonstrate this fact. In the natural, and in the stammering 

 articulation, there is the same total or partial interruption of 

 the expiration, at the same parts, not of the larynx, but of the 

 proper organs of articulation , only in different degrees. Let the 

 larynx be really closed, which may be done after a little trial, 

 and it will immediately be discovered that stammering is, in 

 fact, impossible ; the effort made by the force of the expired 

 air against the parts of the mouth called into action in the 

 articulation of the first class of letters, all escape of air, all 

 noise, become totally interrupted. 



I have just attentively watched the attempts of a stammerer 

 to articulate the various letters. 



In the effort to pronounce the first class of letters, especially 

 the letter T, still more if two T's come together, as in the 

 words THAT TREE, the face became flushed even from 

 interrupted expiration ; yet there was, at every repetition of the 

 effort, a noise audible in the larynx, proving that this part was 

 unclosed. 



In pronouncing the letters of the second class, a repeated 

 hissing noise was distinctly produced by the flow of the com- 

 pressed air, in one case, (F, V,) between the under lip and 

 upper teeth ; in the second, (TH,) between the tongue and 

 upper teeth ; and in the third, (S, Z,) between the teeth. 



In attempting the articulation of some of the letters of the 

 third and fourth classes, and of some of the vowels, the breath 

 was sometimes lost, as it were, in a full and exhausting expi- 

 ration, altogether peculiar. 



All these results prove that the larynx is not closed in stam- 

 mering, and indeed that its closure and stammering are totally 

 incompatible with each other. When expiration is interrupted, 



