THE NERVES AND THEIR FUNCTIONS. 151 



infant's cheek to the last agony of life. It is when the 

 strong man is subdued by this mysterious influence of soul 

 on body, and when the passions may be truly said to tear 

 the breast, that we have the most afflicting picture of human 

 frailty, and the most unequivocal proof, that it is the order 

 of functions we have been considering that is thus affected. 

 In the first struggles of the infant to draw breath, in the 

 man recovering from a state of suffocation, and in the agony 

 of passion, when the breast labours from the influence at the 

 heart, the same system of parts is affected, the same nerves, 

 the same muscles, and the symptoms or characters have a 

 strict resemblance." 



20. FOURTH ORDER. Regular Nerves. I have already 

 stated that there arelthirty pair of regular nerves which go 

 out from the spine/ each nerve being composed of two kinds 

 of fibres ; those of the anterior column being subsidiary to 

 motion, and those from the posterior to sensation. With 

 these, physiologists now class the ffih nerve. This large 

 nerve divides into three principal branches t\\ejirst going to 

 the eye, is called optlialmic) jhe second to the upper jaw, is 

 called superior maxillaryjfaiid the third sent to the lower jaw, 

 is named inferior maxillar^ It is the third branch, how- 

 ever, which is truly a compound nerve, as its roots arise both 

 from the anterior and posterior columns. The inferior 

 maxillary branch, is a nerve of both sense and motion; 

 its filaments of motion supply the muscles which shut the 

 jaw, while those of sensation go to the tongue, salivary 

 glands, gums, teeth of the lower jaw, external ear, cheek, 

 chin, and lower lip. ^It is this nerve) which gives sensibility 

 to the face, and it is this which is the seat of that painful 

 affection called tic dolouroux, which is sometimes removed by 

 cutting the nerve affected. In the cat, the hare, and other 

 .animals with large whiskers, the filaments of this nerve can 

 be traced to the bulbs of the hairs, which accounts for the 

 delicate tact which these animals are endowed with, and by 

 means of which they are enabled to wind their way in the 



