400 NOTICE OF THE LATE SIR CHARLES BELL. 



which he attributed to the want of some competent guide to a knowledge of the 

 principles on which these movements are regulated ; and, perhaps, no other man 

 was so well qualified, by his profound knowledge of anatomy, and his practical 

 acquaintance with art, to supply the want. But he did not confine himself to 

 the illustration of what was useful to the artist ; he also explained how an ac- 

 quaintance with the anatomy of expression might be available to the surgeon or 

 to the physician, in distinguishing the nature or the extent of some important 

 diseases. 



Independent of its intrinsic merit, this work has another interest, for there is 

 reason to suspect that his inquiries into the functions of the nerves in connection 

 with the anatomy of expression led him to prosecute those investigations which 

 terminated in the most remarkable anatomical discovery of our times. 



But before attempting to give an account of Sir CHARLES BELL'S discovery of 

 the different functions of the nerves, corresponding with their relations to different 

 portions of the brain, I must beg your indulgence while I state shortly the opinions 

 upon this subject, which were taught in anatomical schools prior to the announce- 

 ment of his views. This is the more necessary, because these views have now 

 been so generally adopted, both in Great Britain and on the Continent, that we 

 are apt to forget what the previous state of our knowledge really was. And I 

 may perhaps be permitted to make a few preliminary observations, not imme- 

 diately connected with the subject, but which may serve to make it more intel- 

 ligible to such of you as may not have attended to the history of anatomy, and 

 which may also assist us in appreciating the comparative value of the truths 

 which Sir CHARLES was the first to explain. 



In the higher classes of animals, there are three great ramified systems which 

 are distributed to every part of the body. The arteries and veins ; the lacteals 

 and lymphatics ; and the nerves. It is little more than two centuries since we 

 have obtained a tolerably accurate knowledge of the true functions of any of these 

 systems. The earliest anatomists believed, that the arteries in their healthy state 

 contained nothing but ah*, as the name which they still retain denotes ; and the 

 veins were then believed to be the only blood-vessels. In the second century of 

 our era, GALEN is said to have discovered that the arteries also were blood-vessels ; 

 but it was still believed, that there was* a flux and reflux of the blood in the ar- 

 teries and veins, that the blood which flowed through these vessels from the 

 heart or the liver to the extremities, flowed back through the same vessels to the 

 heart and the liver ; and various theories were devised to reconcile this belief, 

 with the natural phenomena which presented themselves. At length in 1628, 

 HARVEY set the question at rest, by publishing his discovery of the circulation of 

 the blood, propelled through the arteries to the extreme parts, and returning 

 through the veins, in two great circles from the right and the left cavities of the 

 heart. 



