on the Structure, Distributio?i, and Functions of the Nerves. 447 



offer a few words in favour of anatomy, as a means better 

 adapted for discovery than experiment. The question lies 

 between observation and experiment, and it may be illustrated 

 by astronomy and chemistry. In the first, the objects being 

 beyond the influence of man, he makes observations, not ex- 

 periments ; and the science at length attains a state of perfec- 

 tion which raises our estimate of the human intellect. In the 

 latter, for the most part, the subjects lie out of the sphere of 

 mutual influence ; they must be brought together by artifice, 

 and chemistry becomes a science of experiment. But anato- 

 my is more allied to the former than to the latter science, in 

 as much as things are obvious to the eyes. In the animal 

 body the parts present distinct textures, and are laid in a na- 

 tural and perfect order ; it is necessary only to trace the tubes 

 or to observe the symmetrical order of the nervous cords, in 

 order to discover their respective uses : the motions, whether 

 of the solid or fluid parts, are so regular and uniform, that the 

 whole offers a subject for observation and induction. Ana- 

 tomy is already looked upon with prejudice by the thoughtless 

 and ignorant : let not its professors unnecessarily incur the 

 censures of the humane. Experiments have never been the 

 means of discovery ; and a survey of what has been attempted 

 of late years in physiology, will prove that the opening of 

 living animals has done more to perpetuate error, than to con- 

 firm the just views taken from the study of anatomy and na- 

 tural motions. 



" In a foreign review of my former papers, the results have 

 been considered as a further proof in favour of experiments. 

 They are, on the contrary, deductions from anatomy ; and I 

 have had recourse to experiments, not to form my own opi- 

 nions, but to impress them upon others. It must be my apo- 

 logy, that my utmost efforts of persuasion were lost, while I 

 urged my statement on the grounds of anatomy. I have made 

 few experiments; they have been simple, and easily perform- 

 ed; and I hope are decisive. 



" If we turn to the opinions which have been entertained on 

 the subject of the brain and nerves, we find one theory to have 

 prevailed from the Greek authors to the time of Willis, and 

 to have descended from him with little alteration, to modern 

 writers. The brain has been supposed to secrete and supply 

 a nervous fluid, and the nerves to be the conduit pipes for its 

 conveyance. In every age the brain has been considered a com- 

 mon sensorium, and all the nerves to be capable of conveying 

 sensation, unless when they had ganglia. If ganglia intervened, 

 then the nerves wnv. said to be cut off from the brain ; and 

 those so distinguished were called vital nerves, neither serving 



tlic 



