218 THE NERVOUS SYSTEM 



18. In this manner the various regions of the body are 

 associated with each other by a nervous apparatus, which is 

 only indirectly connected with the brain and spinal cord, and 

 thus it is arranged that the most widely separated organs of 

 the body are brought into close and active sympathy with each 

 other, so that " if one member suffers, all the other members 

 suffer with it." From this fact, the name sympathetic system, 

 or the great sym^^athetic nerve, has been given to the compli- 

 cated apparatus we have briefly described. Blushing and 

 pallor are caused by mental emotions, as modesty and fear, 

 which produce opposite conditions of the capillaries of the 

 face by means of these sympathetic nerves. ( Head Note 3.) 



19. The Properties of Nervous Tissue. We have seen that 

 in all parts of this system there are only two forms of nervous 

 tissue, namely, the gray substance and the white substance, so 

 called from their difference of color as seen by the naked eye; 



3. The Wonderful Operations of the Sympathetic System. Blush- 

 ing or "Shame-redness." u A blow upon the head will knock a man 

 senseless, but he still lives and survives ; a blow of like violence upon 

 the pit of the stomach is followed by instant death, because the great 

 centre of the organic nerves lies there, and the vital actions are suspended 

 by the blow, so that the system never lives to recover, but abolition of 

 function and of life at once follows. Other actions also belong to this 

 organic nervous system. It controls the caliber of the blood-vessels, for 

 which end filaments run along each of them. The body temperature is 

 maintained by the production arid dispersion of heat thus regulated, a 

 continuous oscillation going on betwixt the internal vessels and those of 

 the skin. It is connected with the emotions ; and so the heart beats per- 

 ceptibly with excitement, and the maiden's cheek blushes before words 

 that should never be spoken, or thoughts that should never arise. The 

 momentary dilatation of the vessels of the skin constitutes the blush (in 

 the German, ' shame-redness '), which is not confined to the face, though 

 of course it is only seen there the body being hid by the clothes." 

 Fotheroill on the Maintenance of Health. 



"There is an old tradition that when the executioner of Charlotte 

 Corday lifted her severed head high in air, and smote the face with his hand, 

 the cheeks were seen to resent the insult with a blush. This reddening is 

 not impossible, for a decapitated head certainly may exhibit, for a time, 

 certain reflex movements. But whether sensibility is retained cannot be 

 known." 



IS. Association of the various regions of the body? If one member suffers ? Blushing? 

 19. Properties of nervous tissue ? Office of the gray substance ? Of the white ? The 

 nervous centres ? White fibres ? 



