September 2, 1897] 



NATURE 



439 



man who, above all others, has showed us how to use it. At 

 the meeting at Montreal a voice from Spain telling of things 

 physiological would have seemed a voice crying out of the wil- 

 derness ; to-day the name of Ramon-y-Cayal is in every physio- 

 logist's mouth. That is one name, but there is yet another. 

 Years ago, when those of us who are now veterans and see signs 

 that it is time for us to stand aside were spelling out the 

 primer of histology, one name was always before us 

 as that of a man who touched every tissue and touched 

 each well. It is a consoling thought to some of us elder ones 

 that histological research seems to be an antidote to senile 

 decay. As the companion of the young Spaniard in the preg- 

 nant work on the histology of the central nervous system done 

 in the eighties and the nineties of the century, must be named the 

 name of the man who was brilliant in the fifties, Albert von 

 KoUiker. 



When I say that the progress of our knowledge of the central 

 nervous system during the past thirteen years has been largely 

 due to the application of the method of Golgi, I do not mean 

 that it, alone and by itself, has done what has been done. 

 That is not the way of science. Almost every thrust forward 

 in science is a resultant of concurrent forces working along 

 difterent lines ; and in most cases at least significant progress 

 comes when efforts from different quarters meet and join hands. 

 And especially as regards methods it is true that their value 

 and effect depend on their coming at their allotted times. As 

 I said above, neither experimental investigation nor clinical 

 observation nor histological inquir)' by the then known methods, 

 had been idle before 1880. They had moreover borne even 

 notable fruits, but one thing was lacking for their fuller fruition. 

 The experimental and clinical results all postulated the exist- 

 ence of clear definite paths for impulses within the central 

 nervous system, of paths moreover which, while clear and sharp, 

 were manifold and, under certain conditions, alternate or even 

 vicarious, and were so constructed that the impulses as they 

 swept along them underwent from time to time — that is, at 

 some place or other — transformations or at least changes in 

 nature. But the "methods of histological investigations avail- 

 able before that of Golgi, though they taught us much, failed 

 to furnish such an analysis of the tangle of grey and white matter 

 as would clearly indicate the paths required. This the method 

 of (iolgi did, or rather is doing. Where gold failed silver has 

 succeeded, and is succeeding. Thanks to the black tract which 

 silver when handled in a certain way leaves behind it in the 

 animal body, as indeed it does elsewhere, we can now 

 trace out, within the central nervous system, the pathway 

 afforded by the nerve cell and the nerve cell alone. We see 

 its dendrites branching out in various directions, each alert 

 to dance the molecular dance assigned to it at once by the 

 more lasting conditions which we call structural, and the more 

 passing ones which we call functional, so soon as some partner 

 touch its hand. We see the body of the cell with its dominant 

 nucleus ready to obey and yet to marshal and command the 

 figure so started. We see the neuraxon prepared to carry that 

 figure along itself, it may be to far-distant parts, it may be to 

 near ones, or to divert it along collaterals, it may be many, or 

 it may be few, or to spread out at once among numerous 

 seemingly equipollent branches. And whether it prove ulti- 

 mately true or no that the figure of the dancing molecules 

 sweeps always onwards along the dendrites towards the nucleus, 

 and always outwards away from the nucleus along the neuraxon, 

 or whatever way in the end be shown to be the exact differences 

 in nature and action between the dendrites and the neuraxon, 

 this at least seems sure, that cell plays upon cell only by such a 

 kind of contact as seems to afford an opportunity for change in 

 the figure of the dance, that is to say, in the nature of the im- 

 pulse, and that in at least the ordinary play it is the terminal of 

 the neuraxon (either of the main core or a collateral) of one cell 

 which touches with a vibrating touch the dendrite or the body 

 of some other cell. We can thus, I say, by the almost magic 

 use of a silver token — I say magic use, for he who for the first 

 time is shown a Golgi preparation is amazed to learn that it js 

 such a sprawling thing as he sees before him which teaches so 

 much, and yet when he comes to use it acquires daily increased 

 confidence in its worth— it is by the use of such a silver token 

 that we have been able to unravel so much of the intricate 

 tangle of the possible paths of nervous impulses. By them- 

 selves, the acquisition of a set of pictures of such black lines 

 would be, of little value. But, and this I venture to think is 

 the important point, to a most remarkable extent, and with 



NO. 1453. VOL. 56] 



noteworthy rapidity, the histological results thus arrived at, 

 aided by analogous results reached by the degeneration method, 

 especially by the newer method akin to that of Golgi, that of 

 Marchi, have confirmed or at times extended and corrected the 

 teachings of experimental investigation and clinical ob- 

 servation. It is this which gives strength to our present 

 position ; we are attacking our problems along two inde- 

 pendent lines. On the one hand we are tracing out anatomical 

 paths, and laying bare the joints of histological machinery ; 

 on the other hand, beginning with the phenomena, and analysing 

 the manifestations of disorder, whether of our own making or 

 no, as well as of order, we are striving to delineate the 

 machinery by help of its action. When the results of the two 

 methods coincide, we may be confident that we are on the road 

 of all truth ; when they disagree, the very disagreement serves 

 as the starting-point for fresh inquiries along the one line or 

 the other. 



Fruitful as have been the labours of the past dozen years, 

 we may rightly consider them as but the earnest of that which 

 is to come ; and those of us who are far down on the slope of 

 life may wistfully look forward to the next meeting of the 

 Association on these Western shores, wondering what marvels 

 will then be told. 



Physiology, even in the narrower sense to which, by em- 

 phasis on the wavering barrier which parts the animal from 

 the plant, it is restricted in this Section, deals with many kinds 

 of being, and with many things in each. But, somewhat as 

 man, in one aspect a tiny fragment of the world, still more of 

 the universe, in another aspect looms so great as to overshadow 

 everything else, so the nervous system, seen from one point 

 of view, is no more than a mere part of the whole organism, 

 but, seen from another point of view, seems by its importance 

 to swallow up all the rest. As man is apt to look upon all 

 other things as mainly subserving his interests and purposes, 

 so the physiologist, but with more justice, may regard all the 

 rest of the body as mainly subserving the welfare of the nervous 

 system ; and, as man was created last, so our natural knowledge 

 of the working of that nervous system has been the latest in 

 its growth. But, if there be any truth in what I have urged 

 to-day, we are witnessing a growth which promises to be as 

 rapid as it has seemed to be delayed. Little spirit of prophecy 

 is needed to foretell that in the not so distant future the teacher 

 of physiology will hurry over the themes on which he now 

 dwells so long, in order that he may have time to expound the 

 most important of all the truths which he has to tell, those 

 which have to do with the manifold workings of the brain. 



And I will be here so bold as to dare to point out that this 

 development of his science must, in the times to come, influence 

 the attitude of the physiologist towards the world, and ought to 

 influence the attitude of the world towards him. I imagine 

 that if a plebiscite, limited even to instructed, I might almost 

 say scientific, men, were taken at the present moment, it would 

 be found that the most prevalent conception of physiology is 

 that it is a something which is in some way an appendage to 

 the art of medicine. That physiology is, and always must be, 

 the basis of the science of healing, is so much a truism that I 

 would not venture to repeat it here were it not that some of 

 those enemies, alike to science and humanity, who are at times 

 called anti-vivisectionists, and whose zeal often outruns, not 

 only discretion, but even truth, have quite recently asserted 

 that I think otherwise. Should such a hallucination ever 

 threaten to possess me, I should only have to turn to the little 

 we yet know of the physiology of the nervous system and 

 remind myself how great a help the results of pure physiological 

 curiosity — I repeat the words, pure physiological curiosity, for 

 curiosity is the mother of science — have been, alike to the 

 surgeon and the physician, in the treatment of those in some 

 way most afflicting maladies, the diseases of the nervous system. 

 No, physiology is, and always must be, the basis of the science 

 of healing; but it is something more. When physiology is 

 dealing with those parts of the body which we call muscular, 

 vascular, glandular tissues and the like, rightly handled she 

 points out the way not only to mend that which is hurt, to 

 repair the damages of bad usage and disease, but so to train the 

 growing tissues and to guide the grown ones as that the best 

 use may be made of them for the purposes of life. She not 

 only heals, she governs and educates. Nor does she do other- 

 wise when she comes to deal with the nervous tissues. Nay, it 

 is the very prerogative of these nervous tissues that their life is 

 above that of all the other tissues, contingent on the environ- 



