338 HOW TO WORK 



think that cells belonging to this class are the organs in which nerve 

 (electrical ?) force originates ; while the triangular cells of the brain 

 and spinal cord already referred to should, I think, be regarded as 

 points in which several currents starting from very different parts 

 decussate, and perhaps where secondary currents are induced in 

 fibres running parallel to those traversed by the primary current, rather 

 than as the actual sources of nerve power. 



Such investigations cannot fail to impress us with the wonderful 

 character of the mechanism concerned in nervous phenomena, and 

 lead us to conclude that the effects produced are to be attributed 

 rather to the mechanism through which force works than to any 

 mysterious or peculiar properties of the force itself. Let no one 

 therefore conclude that anything is gained by regarding nerve force 

 as electricity or some mysterious unknown correlative of ordinary 

 force, of the nature of which we know nothing. If we admit it to 

 be ordinary electricity, the problem is not solved ; for it is obvious 

 that its manifestations are due entirely to the peculiar arrangement of 

 the nerve cells and fibres which constitute the mechanism for setting 

 free and conducting the currents. It is not possible to conceive nerve 

 phenomena without a special nervous apparatus, and it would be 

 absurd to ignore this apparatus in considering the nature of nervous 

 action. The action of the machine cannot be dissociated from its 

 construction. But the construction of the apparatus and its main- 

 tenance in a state fit for action are due to vital power. The lowest, 

 simplest, and least varied kinds of nervous action, like all other 

 actions known in connection with the living elementary parts of 

 living beings, are intimately connected with -vital changes, and 

 cannot be accounted for by physical and chemical laws only. When 

 we ascend to the consideration of the higher and more complex 

 nervous actions, we find reasons for concluding that the vital actions 

 perform a still more important part. In the brain of man we have 

 probably the only example of a mechanism possessing within itself 

 not only the means of repair but the capacity for improvement 

 and the power of increasing the perfection of its mechanism, not 

 only up to the time when the body arrives at maturity, but long 

 after this, and even in advanced life, when many of the lower tissues 

 have undergone serious deterioration, and have long passed the 

 period of their highest functional activity. 



These examples will suffice to show how veiy much our ideas 

 upon broad and highly important general principles may be modified 

 by facts discovered in the course of investigations upon the structure 

 of tissues conducted upon new principles of preparation. It is to 

 be regretted how very little attention is paid to this highly important, 



