XXXIV INTRODUCTION. 



The feelings of light, heat, sound, odor, taste, pressure, are im- 

 mediately followed by physiological effects, as secretion, muscular 

 action, &c. Sensations increase the contractions of the heart, and 

 it has been lately maintained that every sensation contracts the 

 muscular fibres throughout the whole vascular system. The res- 

 piratory muscles also respond to sensations ; the rate of breathing 

 being increased by both pleasurable and painful nerve-impressions. 

 The quantity of sensation, moreover, controls the quantity of emo- 

 tion. Loud sounds produce violent starts, disagreeable tastes cause 

 wry faces, and sharp pains give rise to violent struggles. Even 

 when groans and cries are suppressed, the clenched hands and set 

 teeth show that the muscular excitement is only taking another 

 direction. 



Between the emotions and bodily actions the correlation and 

 equivalence are also equally clear. Moderate actions, like moderate 

 sensations, excite the heart, the vascular system, and the glandular 

 organs. As the emotions rise in strength, however, the various 

 systems of muscles are thrown into action ; and when they reach a 

 certain pitch of intensity, violent convulsive movements ensue. 

 Anger frowns and stamps ; grief wrings its hands ; joy dances and 

 leaps the amount of sensation determining the quantity of correla- 

 tive movement. 



Dr. Carpenter, in his Physiology, has brought forward numerous 

 exemplifications of this principle of the conversion of emotion into 

 movement, as seen in the common workings of human nature. 

 Most persons have experienced the difficulty of sitting still under 

 high excitement of the feelings, and also the relief afforded by 

 walking or active exercise ; while, on the other hand, repression of 

 the movements protracts the emotional excitement. Many irascible 

 persons get relief from their irritated feelings by a hearty explosion 

 of oaths, others by a violent slamming of the door, or a prolonged 

 fit of grumbling. Demonstrative persons habitually expend their 

 feelings in action, while those who manifest them less retain them 

 longer: hence the former are more weak and transient in their 



