528 TOUCH. 



ence to Dr. Wells or the other two physicians, although he shows 

 himself acquainted with Dr. Wells's writings. 1 



" Why are nerves, whose office is to convey sensation, profusely 

 given to muscles, in addition to those motor nerves which are 

 given to excite their motions? To solve this question, we must 

 determine whether muscles have any other purpose to serve 

 than merely to contract under the influence of motor nerves. 

 For if they have reflective influence, and if their condition is to 

 be felt or conceived, it will presently appear that the motor nerves 

 are not suitable internuncii betwixt them and the sensoriurn. I 

 shall first inquire if it be necessary to the governance of the mus- 

 cular frame, that there be a consciousness of the state or degree 

 of action of the muscles? That we have a sense of the condition 

 of the muscles appears from this : that we feel the effects of over- 

 exertion or weariness, and are excruciated by spasms, and feel 

 the irksomeness of continued position. We possess a power of 

 weighing in the hand ; what is this but estimating the muscular 

 force? We are sensible of the most minute changes of muscular 

 exertion, by which we know the position of the body and limbs, 

 when there is no other means of knowledge open to us. Ifa rope- 

 dancer measures his steps by the eye, yet, on the other hand, a 

 blind man can balance his body. In standing, walking, and run- 

 ning, every effort of voluntary power which gives motion to the 

 body is directed by a sense of the condition of the muscles, and 

 without this sense we could not regulate their actions, and a very 

 principal inlet to knowledge would be cut off." 



Weber illustrates this opinion of Dr. Wells, by supporting the 

 hands of a blindfolded person on cushions, and placing unequal 

 weights upon them. If the difference is great, it will be felt. But, if 

 it is small, it will not be noticed till the hands are raised, till 

 the muscles feel what resistance they have to act against. Weber 

 found in most men a more accurate sense of the amount of pres- 

 sure on the left side than on the* right. A minute substance in 

 contact with the skin is always judged to be perpendicularly 

 situated in regard to it, as rays of light are always seen in 3 



1 The British Association has allowed the compiler of the report on the Phy- 

 siology of the Nervous System, to refer to Sir C. Bell alone on this point, with- 

 out any allusion to the previous writings of Dr. Wells, Dr. Brown, or Dr, 

 Spurzheim. 



u Phil. Trans. 1826, 



