448 RECENT PROGRESS IN PHYSIOLOGY. 



reveal themselves more aucl more. This is not the place to enter into 

 details, and I will content myself with pointing- out as illnstrative (»f 

 my theme the progress which is beiug made in our knowledge of how 

 we hear and how sounds affect us. A dozen jM'urs ago we possessed 

 experimental and clinical evidence which led us to believe that auditory 

 imi)ulses sweeping up the auditory nerve became developed into audi- 

 tory sensations through events taking place in the temporosphenoitlal 

 convolution, and we have had some indications that as these passed 

 upward through the lower and middle brain the stritB acusticte and the 

 lateral fillet had some part to play. Beyond this we knew but little. 

 To-day we can with confidence construct a diagram which he who runs 

 can read, showing how the impulses undergoing" a relaj^ in the tuber- 

 culum acusticum and accessory nucleus pass by the stri* acusticte and 

 trapezoid fibers to the superior olive and trapezoid nucleus, and onward 

 by the lateral fillet to the j)osterior corpus quadrageminum and to the 

 cortex of the temporosphenoidal convolution. And if much, very 

 much, yet remains to be done even in tracking out yet more exactly the 

 path pursued by the impulses while they are still undeveloped impulses, 

 not as yet lit up with consciousness, and in understanding the func- 

 tional meaning of relays and apparently alternate routes, to saj^ noth- 

 ing of the deeper problems of when and how the psychical element 

 intervenes, w^e feel that we have in our hands the clue by means of 

 which we may hope to trace out clearly the mechanisms by which, 

 wdiether consciousness plays its part or no, sounds affect so profoundly 

 and so diversely the movements of the body, and haply some time or 

 other to tell, in a plain and exact way, the story of how we hear. I 

 have thus referred to hearing because the problems connected with this 

 seemed, thirteen years ago, so eminently obscure; it appeared so pre- 

 eminently hard a task, that of tracing out a path of an auditory impulse 

 through the confused maze of fiber and cell presented by the lower and 

 middle brain. Of the mechanism of sight we seemed even then to have 

 better knowledge, but how much more clearly do we, so to speak, see 

 vision now ? So, also, with all other sensations, even those most obscure 

 ones of touch and pain; indeed, all over the nervous system light 

 seems breaking in a most remarkable way. 



This great and significant progress we owe, I venture to say, to Golgi — 

 to the method introduced by him 5 and I for one can not help being 

 glad that this important contribution to science, as well as another 

 contingent and most valuable one, the degeneration method of Marchi, 

 should be among the many tokens that Italj", the mother of all sciences 

 in times gone by, is now once more taking her right place in scientific 

 no less than in political life. We owe, I say, this progress to Golgi in 

 the sense that the method introduced by him was the beginning of the 

 new researches. We owe, moreover, to Golgi not the mere technical 

 introduction of the method, but something more. He himself pointed 

 out the theoretical significance of the results which his method pro- 



