September 26, 1901] 



NATURE 



545 



But, although much of early articulate speech may have arisen by 

 the development of interjectional sounds and the reproduction, 

 by the human vocal organs, of natural sounds, it is very unlikely 

 that these afforded the only sources from which words were 

 originally derived. Romanes insists upon this, and, in support 

 of his argument, refers to cases where children invent a language 

 in which apparently imitative sounds take no part. He likewise 

 alludes to the well-known fact that deaf mutes occasionally 

 devise definite sounds which stand for the names of friends. In 

 the light of such evidence, he very properly asks, " Why should 

 it be held impossible for primitive man to have done the same?" 



The value of spoken language, as an instrument of thought, is 

 universally admitted, and it is a matter incapable of contradiction 

 that the higher intellectual eft'orts of man would be absolutely 

 impossible were it not for the support which is afforded by 

 articulate speech. Darwin e.xpresses this well when he says : 

 " A complex train of thought can no more be carried on without 

 the aid of words, whether spoken or silent, than a long calcula- 

 tion without the use of figures or symbols." Such being the 

 case, I think we may conclude that the acquisition of speech 

 has been a dominant factor in determining the high development 

 of the human brain. Speech and mental activity go hand in 

 hand. The one has reacted on the other. The mental effort 

 required for the coining of a new word has been immediately 

 followed by an increased possibility of further intellectual 

 achievement through the additional range given to the mental 

 powers by the enlarged vocabulary. The two processes, 

 mutually supporting each other and leading to progress in the 

 two directions, have unquestionably yielded the chief stimulus to 

 brain development. 



More than one Philologist has insisted that " language begins 

 where interjection ends." For my part I would say that the 

 first word uttered e.xpressive of an external object marked a 

 new era in the history of our early progenitors. At this point 

 the simian or brute-like stage in their developmental career 

 came to an end and the human dynasty endowed with all its 

 intellectual possibilities began. This is no new thought. 

 Romanes clearly states that in the absence of articulation he 

 considers it improbable that man would have made much 

 psychological advance upon the anthropoid ape, and in another 

 place he remarks that " a man-like creature became human by 

 the power of speech." 



The period in the evolution of man at which this important 

 step was taken is a vexed question and one in the solution of 

 which we have little solid ground to go upon beyond the 

 material changes produced in the brain and the consideration of 

 the time that these might reasonably be supposed to take in 

 their development. 



Darwin was inclined to believe that articulate speech came at 

 an early period in the history of the stem-form of man. Romanes 

 gives a realistic picture of an individual decidedly superior to the 

 anthropoid ape, but distinctly below the existing savages. This 

 hypothetical form, half-simian, half-human, was, according to his 

 sponsor, probably erect ; he had arrived at the power of shaping 

 flints as tools, and was a great adept at communicating with his 

 fellows by gesture, vocal tones, and facial grimaces. 



With this accomplished ancestor in his mental eye it is not 

 surprising that Romanes was incHned to consider that articulate 

 speech may have come at a later period than is generally sup- 

 posed. 



At the time that Romanes gave expression to these views he 

 was not acquainted with the very marked structural peculiarities 

 which distinguish the human brain in the region of the speech 

 centre. I do not refer to the development of the brain in other 

 districts, because possibly Romanes might have held that the 

 numerous accomplishments of his speechless ancestor might be 

 sufficient to account for this ; I merely allude to changes which 

 may reasonably be held to have taken place in direct connection 

 with the gradual acquisition of speech. 



These structural characters constitute one of the leading pecu- 

 liarities of the human cerebral cortex, and are totally absent in 

 the brain of the anthropoid ape and of the speechless micro- 

 cephalic idiot. 



Further, it is significant that in certain anthropoid brains a 

 slight advance in the same direction may occasionally be faintly 

 traced, whilst in certain human brains a distinct backward step 

 is sometimes noticeable. The path which has led to this special 

 development is thus in some measure delineated. 



It is certain that these structural additions (o the human brain 

 are no recent acquisition by the stem-form of man, but are the 



NO. 1665, VOL. 64] 



result of a slow evolutionary growth— a growth which has been 

 stimulated by the laborious efforts of countless generations to 

 arrive at the perfect coordination of all the muscular factors 

 which are called into play in the production of articulate speech. 

 Assuming that the acquisition of speech has afforded the chief 

 stimulus to the general development of the brain, and thereby 

 giving it a rank high above any other factor which has operated 

 in the evolution of man, it would be wrong to lose sight of the 

 fact that the first step in this upward movement must have been 

 taken by the brain itself. Some cerebral variation —probably 

 trifling and insignificant at the start, and yet pregnant with the 

 most far-reaching possibilities — has in the stem-form of man 

 contributed that condition which has rendered speech possible. 

 This variation, strengthened and fostered by natural selection, 

 has in the end led to the great double result of a large brain 

 with wide and extensive association areas and articulate speech, 

 the two results being brought about by the mutual reaction of the 

 one process upon the other. 



SECTION I. 



PHYSIOLOGY. 



Opening Address by Prof. John G. McKendrick, M.D., 

 LL.D., F.R.S., President of the Section. 



When the British Association met in Glasgow twenty-five 

 years ago I had the honour of presiding over Physiology, which 

 was then only a sub-section of Section D. The progress of the 

 science during the quarter of a century has been such as to 

 entitle it to the dignity of a Section of its own, and I feel it to be 

 a great honour to be again put in charge of the subject. While 

 twenty-five years form a considerable portion of the life of a man, 

 from some points of view they constitute only a short period in 

 the life of a science. But just as the growth of an organism does 

 not always proceed at the same rate, so is it with the growth of 

 a science. There are times when the application of new methods 

 or the promulgation'of a new theory causes rapid development, 

 and there are other times when progress seems to be slow. But 

 even in these quiet periods there may be steady progress in the 

 accumulation of facts, and in the critical survey of old questions 

 from newer points of view. So far as physiology is concerned, 

 the last quarter of a century has been singularly fruitful, not 

 merely in the gathering in of accurate data by scientific methods 

 of research, but in the way of getting a deeper insight into many 

 of the problems of life. Thus our knowledge of the phenomena 

 of muscular contraction, of the changes in the secreting cell, of 

 the interdependence of organs illustrated by what we now speak of 

 as internal secretion, of the events that occur in the fecundated 

 ovum and in the actively growing cell, of the remarkable pro- 

 cesses connected with the activity of an electrical organ, and of 

 the physiological anatomy of the central nervous organs, is very 

 different from what it was twenty-five years ago. Our know- 

 ledge is now more accurate, it goes deeper into the subject, and 

 it has more of the character of scientific truth. For a long period 

 the generalisations of physiology were so vague, and apparently 

 so much of the nature of more or less happy guesses, that our 

 brethren the physicists and chemists scarcely admitted the sub- 

 ject into the circle of the sciences. Even now we are sometimes 

 reproached with our inability to give a complete solution of 

 physiological problem, such as, for example, what happens in 

 a muscle when it contracts ; and not long ago physiologists 

 were taunted by the remark that the average duration of a 

 physiological theory was about three years. But this view of the 

 matter can only be entertained by those who know very little 

 about the science. They do not form a just conception of the 

 difficulties that surround all physiological investigation, diffi- 

 culties far transcending those relating to research in dead matter ; 

 nor do they recollect that many of the more common phenomena 

 of dead matter are still inadequately explained. What, for 

 example, is the real nature of elasticity ; what occurs in dissolving 

 a little sugar or common salt in water ; what is electrical con- 

 ductivity ? In no domain of science, except in mathematics, is 

 our knowledge absolute ; and physiology shares with the other 

 sciences the possession of problems that, if I may use a paradox, 

 seem to be mMe insoluble the nearer we approach their 

 solution. 



The body of one of the higher animals — say that of man — is a 

 highly complex mechanism, consisting of systems of organs, of 

 individual organs, and of tissues. Physiologists have been able to 

 give an explanation of the more obvious phenomena. Thus 



