544 



NA TURE 



[St;PTIiMKKR 26, I9OI 



This I have done in twenty- ihree skulls chosen at random, ami 

 the result shows that considerable differences in this respect are 

 to he found in different skulls. These discrepancies, however, 

 are sometimes in favour of the one side and at other times in favour 

 of the other side ; and when the combined sectional area for all 

 the skulls examined was calculated it Was, curiously enough, 

 found to be 583^ sq. mm. for the left side and 583 sq. mm. for 

 the right side. 



Leaving out of count the asymmetry in the arrangement of 

 the convolutions in the two hemispheres, which cannot by any 

 amount of ingenuity be twisted into such a form as to give a 

 structural superiority to one side more than the other, the only 

 marked difference which appears to possess any degree of con- 

 stancy is the increase in the territory of the left parietal lobe 

 produced by the more marked depression of its lower frontier 

 line (Sylvian fissure). That this is in any way associated with 

 right-handedness or with the localisation of the active speech 

 centre in the left hemisphere I am not prepared to urge, because 

 the same condition is present in the ape. It is true that some 

 authorities' hold that the ape is right-handed as well as man, but 

 in the gardens of the Royal Zoological Society of Ireland I 

 have had a long and intimate experience of both anthropoid 

 and lower apes, and I have never been able to satisfy myself 

 that they show any decided preference for the use of one arm 

 more than the other. 



That differences do exist in the more intimate structural 

 details of the two hemispheres, which give to the left its func- 

 tional superiority, there cannot be a doubt ; but these have still 

 to be discovered. Bastian has stated that the grey cortex on 

 the left side has a higher specific gravity, but this statement 

 has not as yet received corroboration at the hands of other 

 observers. 



I have already mentioned that man's special endowment, the 

 faculty of speech, is associated with striking changes in that part 

 of the celebral surface in which the motor centre for articulate 

 speech is located. It is questionable whether the acquisition of 

 any other system of associated muscular movements has been 

 accompanied by a more evident cortical change. The centre in 

 question is placed in the lower and back part of the frontal lobe. 

 We have seen that the insular district is covered over in the 

 hinder three-fourths of its extent by the (ronto-parietal and 

 temporal opercula, and thus submerged below the surface and 

 hidden from view. The brain of the ape and also of the micro- 

 cephalic idiot with defective speech goes no further in its 

 development. The front part of the insular district remains 

 uncovered and exposed to view on the surface of the cerebrum. 

 In man, however, two additional opercula grow out and ulti- 

 mately cover over the fore part of trie insula. These opercula 

 belong to the lower and back part of the frontal lobe, and are 

 to be looked upon as being more or less directly called into 

 evidence in connection with the acquisition of aiticulate 

 speech. 



The active speech centre is placed in the left cerebral hemi- 

 sphere. We speak from the left side of the brain, and yet 

 when the corresponding region- on the right side is examined it 

 is found to go through the same developmental steps. 



The stimulus which must have been given to general cerebral 

 growth in the association areas by the gradual acquisition of 

 speech can hardly be exaggerated. 



During the whole course of his evolution there is no possession 

 which man has contrived to acquire which has exercised a 

 stronger influence on his higher development than the power of 

 articulate speech. This priceless gift, " the most human mani- 

 festation ol humanity" — (Huxley) — was not obtained through 

 the exertions of any one individual or group of individuals. It 

 is the result of a slow process of natural growth, and there is 

 no race, no matter how low, savage or uncultured, which does 

 not possess the power of communicating its ideas by means of 

 speech. " If in the present state of the world," says Charma, 

 "some philosopher were to wonder how man ever began to 

 build those houses, palaces and vessels which we see around 

 us, we .should answer that these were not the things that man 

 began with. The savage who first tied the branches of shrubs 



1 Ogle, "On Dextral Preeminence," Trans. Med. CKSrurg. Soc, 1871 ; 

 Aim6 Peie, " Les Courbures lat^rales normales au rachis humain." 

 (Toulouse, iqoo.) 



- Rudinger and others have tried on very unsubstantial grounds to 

 prove that there is a difference in this region on the two sides of the brain. 

 There is, of course, as a rule, marked asymmetiy : but I do not think that 

 it can be said with truth that the cortical de\elopnient of the region is 

 greater on the left side than en the right. 



to make himself a shelter was not an architect, and he who 

 first floated on the trunk of a tree was not the creator of navi- 

 gation." And so it is with speech. Rude and imperfect in its 

 beginnings, it has gradually been elaborated by the successive 

 generations that have practised it. 



The manner in which the faculty of speech originally assumed 

 shape in the early progenitors of man has been much discussed 

 by Philologists and Psychologists, and there is little agreement 

 on the subject. It is obvious that all the more intelligent 

 animals share with man the power of giving expression to certain 

 of the simpler conditions of mind both by vocal sounds and by 

 bodily gestures. These vocal sounds are of the interjectional 

 order, and are expressive of emotions or sensations. Thus the 

 dog is said, as a result of its domestication, to have acquired 

 the power ol emitting four or five different tones, each indicative 

 of a special mental condition and e.ach fully understood by its 

 companions. The common barn-door fowl has also been 

 credited with from nine to twelve distinct vocal sounds, each 

 of which is capable of a special interpretation by its fellows or 

 its chickens. The gestures employed by the lower animals may 

 in certain cases be facial, as expressed by the grimaces of a 

 monkey, or changes in bodily attitude, as we see continually 

 in the dog. 



I think that it may not be unreasonably inferred that in the 

 distant past the remote jirogenitors of man relied upon equally 

 lowly means of communicating with their fellows, and that it 

 was from such humble beginnings that speech has been slowly 

 evolved. 



There cannot be a doubt that this method of communicating 

 by vocal sounds, facial expression and bodily gestures is capable 

 of much elaboration ; and, further, it is possible, as some hold, 

 that it may have attained a considerable degree of perfection 

 before articulate speech began to take form and gradually re- 

 place it. Much of it indeed remains with us to the present 

 day. A shrug of the shoulders may be more eloquent than the 

 most carefully prepared phrase ; an appropriate expression of 

 face, accompanied by a suitable ejaculation, may be more 

 withering than a flood of invective. Captain Burton tells us 

 of a tribe of North American Indians whose vocabulary is so 

 scanty that they can hardly carry on a conversation in the dark. 

 This and other facts have led Mr. Tylor, to whom we owe so 

 much in connection with the early history of man, to remark : 

 *' The array of evidence in favour of the existence of tribes 

 whose language is incomplete without the help of gesture-signs, 

 even for things of ordinary import, is very remarkable " ; and, 

 further, " that this constitutes a telling argument in favour of 

 the theory that gesture-Unguage is the original utterance of 

 mankind out of which speech has developed itself more or less 

 fully among different tribes." It is a significant fact also, as 

 the same author points out, that gesture-language is, to a large 

 extent, the same all the world over. 



Many of the words employed in early speech were undoubtedly 

 formed, in the first instance, through the tendency of man to 

 imitate the natural sounds he heard around him. To these 

 sounds, with various modifications, was assigned a special con- 

 ventional value, and they were then added to the growing 

 vocabulary. By this means a very decided forward step was 

 taken, and now primitive man became capable of giving utter- 

 ance to his perceptions by imitative sounds. 



Max Midler, although bitterly opposed to the line of thought 

 adopted by the " Imitative School " of philologists, has ex- 

 pressed their views so well that I am tempted to use the words 

 he employed in explaining what he satirically branded as the 

 "Bow-wow Theory." He says: "It is supposed that man, 

 being yet mute, heard the voices of the birds, dogs, and cows, 

 the roaring of the sea, the rustling of the forest, the murmur of 

 the brook, and the whisper of the breeze. He tried to imitate 

 these sounds, and finding his mimicking cries useful as signs of 

 the object from which they proceeded, he followed up the idea 

 and elaborated language." 



Hood ' humorously and unconsciously illustrates this doctrine 

 by a verse descriptive of an Englishman, ignorant of French, 

 endeavouring to obtain a meal in France : — 



" ' Moo : ■ I cried for milk ; 

 If 1 wanted bread 

 My jaws 1 set agoing : 

 And asked for new-laid eggs_ 

 By clapping hands and crowing." 



Quoted from "The Origin of Language," by Hensleigh Wedgwood, 



NO. 1665, VOL. 64] 



