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Not having at our disposal sufficient data for racial comparisons of brain weight, let us see if the skull capacity can not supply them. We know, since the investigations of Manouvrier, that we have only to multiply by the coefficient 0.87 the capacity in cubic centimeters of the cranial cavity to get with reasonable exactitude the weight in grams of the brain which it contained. Now the following is what we learn from the figures of cranial capacity brought together by Topinard. . . . Among Europeans the average capacity for men is 1565 c.c., varying from 1530 c.c. (22 Dutch) to 1601 c.c. (43 Finns). The capacity for peoples of other continents we find to range from 1583 c.c. (26 Eskimo) down to 1349 c.c. (36 Australians) and 1310 c.c. (11 Andaman Islanders). Between these two extremes the other populations would be thus arranged in a decreasing order of capacity: 36 Polynesians, 1525 c.c.; 18 Javanese, 1500 c.c.; 32 Mongols, 1504 c.c.; 23 Melanesians, 1460 c.c.; 74 Negroes, 1441 c.c.; and 17 Dravidians of Southern India, 1353 c.c. The difference between the highest and lowest of these figures for non-Europeans is 255 c.c., or a little more than the difference between man and woman in all races.

Manouvrier gives the following weights, converted from cranial capacities: 187 modern Parisians, 1357 grams; 61 Basques, 1360 grams; 31 Negroes, 1238 grams; 23 New Caledonians (Melanesians), 1270 grams; 110 Polynesians, 1380 grams; and 50 Bengalis, 1184 grams. The difference of the extremes here is 196 grams.

Must we recognize in these racial differences of brain size and weight the influence of stature and bulk of body, as appears unquestionable for the sex difference? One is tempted to believe this when one sees that the largest brain weight in Europe, 1417 grams (157 brains), is found among the Scotch, whose stature is the highest in the human species; and that the mean brain weight of Italians (244 cases), whose average stature is rather small, is only 1308 grams. The Polynesians and Caucasians, peoples of high stature, also outweigh the Andaman Islanders and Javanese, of very low stature. However, we see, on considering both brain weights and cranial capacity, that Negro populations of very high stature, also the Australians and New Caledonians of medium stature, have a smaller cerebral weight than the short Eskimo and certain low statured Asiatics like the Javanese.

There is thus a double influence: that of stature and that of race. We might introduce a third element-the weight of the body; but it represents too many different things, varying according to the individual's inclination towards stoutness, his diet, and mode of life. C. Voit, experimenting on two dogs of nearly equal bulk, found that the weight of the brain of the well-fed dog represented 1.1 per cent of the weight of its body, while the brain of the dog that had fasted twenty-two days constituted 1.7 per cent of the weight of the body. At all events, we cannot

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deny the influence of the bulk of the active parts of the body on the volume of the brain.

But then a new question arises. Is the increase of the volume of the brain made at the cost of the white substance formed solely of conductingfibres; or of the gray cortex substance formed principally of cells with their prolongations (neurons), that is to say, the part which is exclusively involved in mental processes? This question still awaits its solution. It is not the gross weight of the brain, but really the weight of the cortical layer which should be compared in the different races and subjects, if one is to judge of the quantity of substance devoted to mental functions. Until the necessarily very delicate weighings of this kind shall have been actually made, we have only a round-about method of ascertaining the quantity of the gray substance: by measuring the superficial area which it occupies.

The cerebral cortex, composed of the gray matter, forms on the surface of the brain sinuous folds called cerebral convolutions. Now, in brains of equal volume, the more numerous, sinuous, and complicated these folds, the greater will be the surface of the cortex. As the thickness of the gray layer is very much the same in all brains, it is evident that the complexity in the structure of the convolutions corresponds to the increase of the gray substance, and consequently of mental force. Now, the little that is known of the cerebral convolutions in different races, and of various persons in the same race, appears to conform to this deduction. The brains of idiots, of the feeble-minded, present very simple convolutions, almost comparable to those of the anthropoid apes, whose brain is like a simplified diagram of the human brain. On the other hand, distinguished personages, great scholars, orators, men of action, exhibit a complexity, sometimes truly remarkable, of certain convolutions.

I expressly say "certain" convolutions, for all these folds, which are arranged according to a plan common to all human beings, do not have the same value physiologically. In the gray layer of certain of these convolutions are the centers of motor impulses and of general bodily sensibility; for example, those which are arranged around the fissure of Rolando. Some of these regulate the voluntary movements of the limbs, trunk, and head; while others are connected with visual, auditory, gustatory, olfactory sensations. These various motor and sensorial regionscenters of projection, they are called-make up nearly a third of the gray matter of the brain. But there are a great many other convolutions, the gray matter of which is unconnected with any special function. What is their purpose? Basing his opinion on the tardy myelinisation of the nerve fibers ending in these convolutions, subsequent to birth and to the myelinisation of the sensory and motor center fibers, Flechsig supposes

Formation of the white sheath of nerve fibers.

that these convolutions are designed to enable the different brain centers to communicate with one another and to render us conscious of this communication. Therefore he has named their gray substance "centers of association." Without these convolutions, the other centers would remain isolated and condemned to a very restricted activity.

Now, as the eminent anatomist Turner has shown so clearly, the convolutions of the sensory and motor centers do not present any great differences in the brain of a child, a monkey, a Bushman, or of a European man of science like Gauss. What differentiates these brains is the degree of complexity of the convolutions concerned with association. It follows, then, that the parts of the brain available for comparison-the associational parts are less than the whole by the motor and sensory regionsa third of the brain cortex.

But let us suppose that differences of volume and weight are found in these associational two-thirds of the gray matter. Have we more reason to think that we are approaching a solution of the problem? Hardly. It is believed that only certain cells of the gray substance, namely, the great and little pyramidal-shaped cells, are associated with mental activity. Each of these, forming with its axis-cylinder, dendrons, and other branching prolongations what is called a neuron, is believed not to be in constant connection with other neurons, nor to occupy a fixed permanent position in regard to them, but, by means of its prolongations, to place itself alternately in contact with a great number of them.

The nervous currents resulting from these continual changes of contact must be extremely complex. Thus cerebral activity would very likely have to be measured not merely by the number and size of the gray matter cells, but also by the number and variety of habitual contacts which are probably established after education or training of the cells. As from the same number of piano keys the novice can produce only a few simple strains, while an artist elicits varied melodies, so from a practically equal number of cells a savage would be able to extract only vague and rudimentary ideas, while a thinker would bring intellectual treasures out of them.

How far from a true appreciation of brain functioning are we then with our rude weighings of the organ; when, together with the quarter that would assuredly help us solve our problem, we must weigh three other quarters that have nothing or almost nothing to do with cerebration! And even if we succeeded in finding the number, weight, and volume of the neurons, how are we to estimate the innumerable combinations of which they are capable? The problem appears almost insoluble.

However, in science we must never lose hope, and-who knows?perhaps some day the solution of the question will be found, and may then appear as simple as to-day it appears a matter of course to see through the body with the X-ray.

17. RACE, LANGUAGE AND NATIONALITY IN EUROPE'

By HUMPHREY J. JOHNSON

Of the various physical characteristics which mark off the different branches of mankind from each other the colour of the skin is that which most easily attracts the eye of an observer; hence it was most natural that the early attempts to classify the races of man should have been made upon this basis. In the 18th century Linnaeus assigned to "Homo Europaeus albus" the position of being one of his four primary divisions of the human species. The name was not strictly accurate, however, as under it there had to be tabulated the populations of North Africa and South-western Asia, which were little if any darker than the peoples of Southern Europe. In the early 19th century Blumenbach gave to the white-skinned peoples of Europe, Asia and Africa the name Caucasian, after a skull from Georgia which he greatly admired. This name has lasted long, and is still in use, but since it has to include such peoples as the dark Arabs and the fair Swedes, some further division of the white race was recognised to be a necessity. This step was taken by Huxley, who in 1870 divided into two stocks "fair whites" (xanthochroi) and "dark whites" (melanochroi). The two stocks overlapped in Central Europe, and Celtic speaking peoples were found belonging to both. Of these two Huxley supposed that the xanthochroi of Northern Europe were the original stock and that the melanochroi of the Mediterranean area were produced by intermixture between the former and a brown race. At this time, however, the problem of devising a satisfactory method of classifying the population of Europe was complicated by that confusion between philological and anthropological terms which has wrought such dire havoc with ethnological nomenclature. Comparative philology had made it clear that with few exceptions all the languages of Europe could be traced back to a single ancestral stock, offshoots of which had also found their way into Persia and India. This family of languages received the names "Aryan," "Indo-European" or "Indo-Germanic," and it began to be readily assumed that there must have existed an Aryan race, a doctrine which still lingers in modern geography books. No one, however, could say whether the early Aryans were dark whites or fair whites. Max Müller ventured to launch the opinion that their original "habitat" had been "somewhere" in Asia, though he later abandoned the hypothesis that an Aryan race had existed. With the exception of Greek and

'The Sociological Review, volume 11, pages 37-46, 1919.

Albanian, the Aryan languages of Europe fall into four groups-Romance, Celtic, Teutonic, and Letto-Slavic.

It has of course always been known that the Romance languages owe their present distribution not to the circumstance that they were carried to the lands in which they now prevail by a single race, but to the fact that these lands were once under the influence of a common civilization. Hence, although we meet the expression "Latin race" in newspapers and reviews, we do not encounter it in manuals of ethnology. The origin, growth and distribution of the Celtic, Teutonic and Slavic branches of the Aryan family are, however, shrouded in much obscurity, and this fact has enabled writers to employ these terms now in a linguistic and now in an ethnological sense. The tall fair-haired barbarians who swarmed down from the Alps upon the Italian plains were called by the classical writers Celts, though in the first century before the Christian era, at the time of Cæsar's conquest of Gaul, a distinction between the Celts and the Teutons began to be made. The Slavs do not, however, figure prominently in European history till Byzantine times. The precedent set by the classical writers was followed, and it was customary to regard the Celts as a fairhaired race, till about 1850, when Broca, who was then conducting his anthropometrical researches into the composition of the French nation, showed that the Bretons--the only Celtic speaking people on the continent of Europe had dark hair, from which discovery it followed that a distinction must be made between the use of the word Celtic as a linguistic and an anthropological term.

The recognition of this fact has simplified the work of subsequent investigators, and in the two most comprehensive attempts to classify the European peoples which have been made in recent years, those of Ripley and Deniker, "Celtic" does not appear as a racial term. These two investigators, fully alive to the errors into which their predecessors have fallen through failing to distinguish clearly between language and race, have attempted to systematize the European peoples solely by the use of physical criteria. Their results are at first sight strikingly dissimilar, although they have been reached by the use of almost identical material. Professor Ripley recognises three European races: (1) a tall, fair-haired dolichocephalic race, which predominates in the countries bordering upon the Baltic and the North Sea, which he names the Teutonic race; (2) a brachycephalic race of medium height, brown hair and eyes, stretching from Brittany through the highlands of Central Europe, the plateau of Central France, the Auvergne and Vosges through South Germany, Switzerland, the Austrian Empire and the Balkan states, across the sea of Marmora, through Asia Minor and Armenia to Persia and Afghanistan. This race he names the Alpine; and (3) a short, dark-haired, dark-eyed dolichocephalic race, which is found in the lands lying round

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