THE NERVOUS SYSTEM. 85 



might render comfortable all the poor in the United States by pur- 

 chasing farms for their use. Strange it is, and it shows the per- 

 version of our best feelings, that almost everybody worships this 

 wretched old man, not for his good traits, but for his money ! ! 



Well might the Apostle say, " Go to, ye rich men, weep and howl 

 for the miseries that shall come upon you." This state of things 

 here, and more especially in Europe, fulfils the prediction of Pol- 

 lock in his Course of Time, where he says, 



" Starving want in time of wealth." 



CHAPTER VI. 



THE NERVOUS SYSTEM. 



WE have now to enter on the consideration of those parts that 

 essentially distinguish an animal from a vegetable, and the organs 

 of the animal from those belonging to the organic life ; or, in other 

 words, we have to speak of the parts that give us the power of 

 voluntary motion, and which enable us to feel and to think. 



In all but the most simple animals, it is quite certain that sensa- 

 tion and voluntary motion depend on the nervous system. The 

 nervous system of man consists of the brain, the spinal marrow, 

 and the nerves. As these are all composed of nearly the same kind 

 of substance, we may view the spinal marrow and brain as nervous 

 matter collected into masses, and the nerves as the same matter dif- 

 fused over every part of the body.- The brain, as has already been 

 mentioned, is contained in and protected by the cranium or skull. 

 It is also enclosed in three layers of fine membrane, the outermost 

 of which (dura mater) is strong and tough, and adheres to the skull 

 at different points ; the middle layer (arachnoid) is so fine as 

 scarcely to be visible ; and the innermost one (pia mater) not only 

 envelopes the brain, but also penetrates into certain parts in its 

 interior. The spinal marrow has similar coverings, and is con- 

 tained in the canal formed by the rings of the united vertebrae. 

 The nerves are cords, attached to the brain and spinal marrow, 

 which are composed of brainy matter enclosed in numerous minute 



