422 PHYSIOLOGY 



stand the experimental method, whatever may be the character of 

 its technique, then the question suggested above becomes relatively 

 simple. This, I believe, is the standpoint assumed by the founders 

 of modern physiology, and this is the truth which they wished to 

 emphasize when they claimed that physiology is essentially an 

 experimental science which must develop along lines similar to 

 those worked out in physics and chemistry. When Magendie com- 

 pleted the demonstration of the division of function between the 

 anterior and the posterior roots of the spinal nerves, a distinction 

 that had been assumed by Bell on anatomical grounds, he used the 

 chemical and physical method; he stimulated each root, and thus 

 arrived at a positive conclusion which could never have been reached 

 except by the employment of the experimental method. And those 

 observers like Langley, who in our own day "are slowly unraveling 

 the physiological mechanism of the so-called sympathetic or auto- 

 nomic nervous system and are using experimental stimulation at 

 every stage of the work, are also in this sense employing the physical 

 and chemical method. From this point of view there is no room for 

 criticism regarding the progress, past or future, of the science of 

 physiology. Most of our advance in knowledge has been due to 

 direct experimental inquiry, and the opportunities for further satis- 

 factory work of the same character are lacking only to those who 

 fail in the zeal or talent requisite to imagine and carry out experi- 

 mental investigations. A recent writer 1 has said, "He who cannot 

 discover and classify new facts in any branch of natural science 

 after a few weeks, or at most a few months, of industrious work 

 must indeed be ignorant or unskilled." As regards experimental 

 physiology, I cannot agree with this author in the implied sim- 

 plicity of the task of discovery of new facts. I fancy that the 

 unpublished history of the subject contains records of many inves- 

 tigations which were carried out by observers neither ignorant nor 

 unskilled, but which failed to unearth any new facts. But this 

 much seems to me to be certain, that in physiology at present there 

 is abundant opportunity for every grade of investigation. The 

 subject is not so far advanced that new facts of even the simplest 

 kind are without value. That purely anatomical studies may have 

 a profound influence upon physiological theories is illustrated in the 

 most striking way by the history of the so-called neurone doctrine 

 and by the modified views upon this subject that are beginning to 

 be felt in consequence of the anatomical work of Apathy, Nissl, 

 Bethe, and others. For physiology, however, it is all-important that 

 the ideas suggested from the anatomical side shall be verified and 

 expanded by the experimental method. Bethe's experimental 



1 Ostwald, The Relations of Biology and the Neighboring Sciences, University 

 of California Publications, Physiology, i, p. 11, 1903. 



