THE NERVOUS SYSTEM. 135 



210. After the numerous experiments* mad by 

 Ilaller and other very careful observers, we are cer- 

 tain, from minute anatomical examination, that many 

 of the similar parts do not exhibit any true vestige of 

 nerves ; and from surgical observation t and dissections 

 ef living animals, J that they do not evince the least 

 sign of feeling. 



* Hallcr on the sensible parts of the body, Comment. Sot: Sc. Gotting. T. i. 

 and his discourse upon them, Xov. Comment. Gutting. T. iii. 



Peter Castcll, E.rperim. quibus count It it varias h. c. partcs sentiendi facilitate 

 carer e. Getting. 1753. 4to. And three entire collections on the controversies 

 excited by the Gottmsren publications throughout Europe. 



Suir itiseasibilita e irritalilita, disserta:ioni transportate da J. G. V. Petrini. 

 Rom. 1753. 4to. 



Sulla MscH.iifivita cd irritabilita Hallcriana opuscoli raccolti da G. B. Fabri. 

 Bologna. 1757 59. IV vol. 4to. And that which Haller himself published 

 under the title of Mewoires sur la nature sensible et irritable des parties du corps 

 humaiii. Lausanne. 1756 59. IV vol. 12mo. 



f Amidst the great variety and even contradiction of opinion, which, as we shall 

 presently mention, exists with respect to the feeling of tendons and other parts 

 when injured, I have always considered negative arguments of more weight 

 than positive, because nothing is more fallacious than the ideas of patients as to 

 the seat of internal pains. To say nothing of cases where amputated parts 

 appear to the patient as still in possession of iceling, it is well known that some 

 have felt a fixed pain for a great length of time in parts where after death 

 nothing uncommon was observable ; and that, on the other hand, in chronic 

 diseases, pain is sometimes felt not in the diseased part, but in another which is 

 healthy and perhaps very remote. 



We may in this way much more easily explain syphilitic pains, for instance, 

 referred to the bones, than the result of so many contradictory experiments, in 

 which I have seen the medulla of the human subject roughly handled without 

 causing the least uneasiness. 



J I am every day more convinced that much caution, and practice, and re- 

 petition of the same experiment in many different kinds of animals, are neces- 

 sary in establishing the laws of physiology from dissections of living animals. 

 To adduce the example of the supposed feeling of the medulla, I have found 

 different results in many mammalia and birds. Many allowed the medulla to 

 be destroyed without evincing any symptom of pain ; others were convulsed, 



