THE 



BRAIN AS AN ORGAN OF MIND. 



CHAPTER I. 



THE USES AND ORIGIN OF A NERVOUS SYSTEM. 



A LIFELESS object makes no appreciable response to ex- 

 ternal impressions. If we touch a rock or a stone, no 

 answering movements follow. Day and night, summer 

 and winter succeed one another, and yet, though inaui- 

 mate objects undergo imperceptible molecular changes, 

 they yield no active and visible response either to diurnal 

 or to seasonal vicissitudes. 



It is wholly different, as we know, with the members 

 of the vegetable kingdom existing around and amongst 

 these inanimate things. The seasonal changes shown by 

 them are familiar to all. The putting forth of the leaf, 

 the period of active growth, the bloom of flowers, the 

 shedding of seed, the fading and fall of leaves, are so 

 many manifestations of an internal activity which dis- 

 play themselves with never-failing regularity. 



