52 Prof. Muller and Dr. M. Hall 



*' Of the Reflexion in the Motions after Perceptions. 



" The observations which are brought forward in this Chap- 

 ter are new, and denote a remarkable progress in our science. 

 They relate to phoenomena of the so-named sympathetic mo- 

 tions after perceptions, which were formerly very liberally sup- 

 posed to be exercised by the sympathetic nerve, though it may 

 be clearly proved that they take place quite independently of 

 it. As the phasnomena belonging to this class are uncommonly 

 numerous, and include a great part of the phaenomena which 

 were formerly without any proof attributed to the sympathetic 

 nerve, the use of the sympathetic nerve in the explanation of 

 nervous sympathies seems constantly to diminish. How much 

 this part of physiology has altered, is clearly seen, by com- 

 paring the explanation of a great part of the nervous sympa- 

 thies which the admirable Tiedemann investigated in the year 

 1S25*. The explanations of the sympathies by means of the 

 sympathetic nerve, in fact, explain everything and yet nothing. 

 Thus, as this work will fully show, the most evident and fre- 

 quent sympathies between the uterus and mammae, the paro- 

 tid and testes, the larynx and testes, are quite inaccessible to 

 these explanations. We will not positively say that the sym- 

 pathetic nerve does not take a part in any of the sympathetic 

 phaenomena, but we do altogether deny that the sympathetic 

 nerve participates in all the so-called sympathetic phaenomena, 

 which will be examined in this chapter, and we think it very 

 probable that the sympathetic nerve is generally unconnected 

 with the greatest part of those sympathies, in which motions 

 take place after perceptions, or perceptions after other percep- 

 tions, or motions after motions. The explanation of sympa- 

 thies by nervous connexions had been already made very ques- 

 tionable by the microscopic anatomy of their primitive fila- 

 ments. For how could this explanation be received, when at 

 present, though we know of connexions of the fasciculi of the 

 nerves, we are acquainted with no union of their primitive 

 filaments? A mere nervous connexion, therefore, without any 

 ganglion on the part, cannot of itself in the present state of 

 the science explain any sympathy. 



" The phaenomena now to be examined were observed at 

 nearly the same time by Dr. Marshall Hall and myself. As 

 the greatest part of the ' Nervenphysik/ as here given, was 

 completely prepared several years since, so also this Chapter 

 on the reflected motions after perceptions, was written down 

 almost exactly as here given several years ago. That this 



• Zeitschrift fiir Physiologic, i. 



