WHY WE LAUGH WITH THE ORGANS OF SPEECH. 201 



ends ; as when we try to escape a danger, or struggle tc 

 Becure a gratification. But the movements of chest and 

 limbs which we make when laughing have no object. And 

 now remark that these quasi-convulsive contractions of the 

 muscles, having no object, but being results of an uncon- 

 trolled discharge of energy, we may see whence arise their 

 special characters — how it happens that certain classes of 

 muscles are affected first, and then certain other classes. 

 For an overflow of nerve-force, undirected by any motive, 

 will manifestly take first the most habitual routes ; and if 

 these do not suffice, will next overflow into the less habit- 

 ual ones. Well, it is through the organs of speech that 

 feehng passes into movement with the greatest frequency. 

 The jaws, tongue, and lips are used not only to express 

 strong irritation or gratification ; but that very moderate 

 flow of mental energy which accompanies ordinary conver- 

 sation, finds its chief vent through this channel. Hence it 

 happens that certain muscles round the mouth, small and 

 easy to move, are the first to contract under pleasurable 

 emotion. The class of muscles which, next after those of 

 articulation, are most constantly set in action (or extra ac- 

 tion, we should say) by feelings of all kinds, are those of 

 respiration. Under pleasurable or painful sensations we 

 breathe more rapidly : possibly as a consequence of the in- 

 creased demand for oxygenated blood. The sensations 

 that accompany exertion also bring on hard- breathing ; 

 which here more evidently responds to the physiological 

 needs. And emotions, too, agreeable and disagreeable, 

 both, at first, excite respiration ; though the last subse- 

 quently depress it. That is to say, of the bodily muscles, 

 the respiratory are more constantly implicated than any 

 others in those various acts which our feelings impel us to ; 

 and, hence, when there occurs an undirected discharge of 

 nervous energy into the muscular system, it happens that, 

 if the quantity be considerable, it convulses not only cer- 

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