404 NOTICE OF THE LATE SIR CHARLES BELL. 



wards and forwards along the same cord, continued to be taught, or was left to 

 be inferred, by all the teachers of Europe, for at least a year after Sir CHARLES 

 BELL had announced to his friends his ideas on the nervous system. 



To the genius and to the patient and laborious investigations of Sir CHARLES 

 BELL we owe the discovery, that no one nerve serves the double purpose of minis- 

 tering to motion and to sensation ; that the spinal nerves and the fifth nerve of 

 the brain, which had been regarded each as one nerve, consisted each of two dis- 

 tinct nerves, connected with different portions of the brain, enclosed in one sheath 

 for the convenience of distribution, but performing different functions in the ani- 

 mal economy, corresponding with the different portions or tracts of the brain to 

 which they could be traced ; the one conveying the mandates of the will to the 

 muscles of voluntary motion from the sensorium, the other conveying to the sen- 

 sorium intelligence of the condition of distant parts, or sensation. That, to use 

 the illustration I have already employed, as the arteries carry the blood from the 

 heart and the veins carry it to the heart, so one set of nerves carry the impulses 

 of volition from the brain, and another set of nerves carry the impulses of sensa- 

 tion to the brain ; that the brain is divided, together with the spinal marrow 

 Avhich is prolonged from it, into separate parts, ministering to the distinct func- 

 tions of motion and sensation ; and that the origin of the nerves, from one or 

 other of these sources, seems to endow them with the particular property of the 

 division whence they spring. Such were the leading features of BELL'S great 

 discovery, one of the most remarkable that the history of anatomy will now have 

 to record. 



Let us not forget that the steps by which human knowledge has advanced 

 have at all times been short and slow. It has rarely or never been permitted to 

 the same mind to originate the idea, and to perfect the development of any of the 

 great truths of nature. The greatest discoveries in science have either been dimly 

 seen at a distance and imperfectly shadowed forth, or coniectured as matters of 

 speculation, or the minor truths on which they are founded have been divulged 

 by those who went before, but who failed to arrive at the conclusion which opens 

 up to our view what till then had been hidden, and which expounds to us one of 

 the great laws of nature. But it is to him who, pressing on in advance of his 

 fellows, takes this last and greatest step, and establishes the truth on a sure foun- 

 dation, making it practically available to other men, a permanent contribution 

 to human knowledge, and a fresh illustration of the perfection of created things, 

 that we justly attribute the glory of a discovery ; and to that glory Sir CHARLES 

 BELL is justly entitled. 



The circulation of the blood through the lungs was known to GALEN and to 

 many of his successors ; and it was demonstrated by COLUMBUS, the disciple of 

 VESALIUS. CJESALPINUS not only knew the circulation through the lungs, but he 

 also discovered that there was a communication between the extreme branches of 





