exists in the brain, and that volition pro- 

 ceeds from that organ, it riecessarily fol- 

 lows that motions must be transmitted to and 

 fro along the nervous chords, wheilever they 

 take place. It was formerly supposed 

 that these chords were passive, and might 

 be made mechanically to vibrate, but 

 their want of elasticity and tension, and 

 their pulpy origins and terminations, are 

 circumstances which render such a sup- 

 position inadmissible. Physiologists were 

 therefore led to conjecture that the ner- 

 vous fibrils were tubular, and that they 

 contained a subtile fluid, by means of 

 which such motions were transmitted. 



Of the extensive knowledge and high 

 intellectual powers of Baron Haller fto 

 one can entertain a doubt; and yet, he 

 could devise no other theory to account 

 for the phenomena of the nervous func- 

 tions. His opinions have always appear- 



