44(5 VIVISECTION. 



specific use to them. When he began'jhis neurine inquiries, 

 the prevalent belief in the use of ganglions was, that they 

 were endowed with the function of cutting off the power or 

 faculty of sensation from any nerve upon which they might 

 exist, leaving such nerve endowed with the faculty of motion 

 only. 



Slightly to anticipate the development to which a syste- 

 matic inquiry into the experiments and conclusions of Sir 

 Charles Bell on the nervous system would lead, it will be 

 convenient to announce, in this place, that the great British 

 physiologist's experiments led him to a deduction the very- 

 converse of that assigned by prevalent belief concerning the 

 use and endowment of nervous ganglions. He proved the 

 posterior or ganglionated root of a spinal nerve to be made 

 up of sensitive fibres exclusively; whereas the anterior or 

 non-ganglionated root he proved to be made up of motor 

 fibres exclusively. Next, having extended his inquiries to 

 the cerebral nerves, he eventually came to the conclusion 

 that, functionally regarded, they were symmetrical with the 

 spinal nerves; differing from the latter in mechanical ar- 

 rangement of parts truly, but conforming to the typical ordi- 

 nance that sensitive nervous fibre should ever be associated 

 with ganglionic nervous matter. 



Here, then, was effected not only a very grand but a very 

 clear physiological discovery. It has nothing veiled, misty, 

 or indeterminate about it. The truth stands revealed in 

 sharp-cut prominent outlines. It is comparable, in this re- 

 spect, to any geometrical truth, such as the equality between 

 the three angles of a triangle and a pair of right angles, or 

 the equality between a large square on the hypothenuse and 

 the sum of the two small squares on the two sides of a right- 

 angled triangle. The demonstration accomplished by Sir 

 Charles Bell, moreover, so far from having been prompted or 

 led up to by discoveries that had preceded him, and opinions 

 founded thereon, was diametrically opposed to the latter, 



