Pedagogical Anthropology

The nature of the transformations undergone by the skeleton of the trunk in relation to its different parts is substantially as follows: in the child at birth the vertebral column is straight, and the thorax is higher up than in the adult; the pelvis, on the contrary, slants forward and downward. In the adult the vertebral column is curved in the form of an S, showing the two-familiar dorsal-lumbar curves, and the axes of the thorax and pelvis are more perceptibly horizontal; in short, in the course of growth a descent of the thorax has taken place, together with a rotation of the pelvis (Fig. 124).

A. Descent of the Thorax.—This is the chief of these characteristics: the thorax descends in the course of its growth.

In the new-born child the upper edge of the manubrium of the sternum is in juxtaposition to the body of the first dorsal vertebra, while in the adult it is situated on a level with the lower edge of the second vertebra.

Even the tendinous arch of the diaphragm has shifted, being lowered by the space of a vertebra; it is situated between the eighth and ninth vertebræ in the child at birth, and between the ninth and tenth in the adult.

The outside characteristics are in correspondence with this fact; the shoulders descend in the course of growth. In the adult, the acromia or points of the shoulders are on a lower level than the incisura or cleft in the sternum (which is visible at the anterior base of the neck, and may be felt as an indented half-moon); while in the new-born child, on the contrary, the shoulders are higher up than the upper extremity of the sternum.

Another external characteristic of the descent of the thorax is the change in position of the nipples at successive ages; the mammary papillæ of the adult correspond to the level of the lower extremity of the sternum, and are situated respectively at the central points of the two halves of the thorax; in the new-born child, on the contrary, the mammary papillæ are further apart and higher up.

These characteristics of the descent of the thorax are fully established in the period of puberty and are of great importance, since, if not completed, they indicate cases of arrest of development or infantilism.

Quétélet has made a study of the triangulation of the thorax (Fig. 125).

If the two nipples and the sternal incisura are connected by straight lines inclosing an isosceles triangle ABB´, the length of the base in the new-born child is 70 millimetres, and that of the sides BA, B´A is 54 millimetres, and the height 41 millimetres.

In the adult the dimensions are as follows: BB´ = 197 millimetres; AB, AB´= 184 millimetres; and the height = 155 millimetres. Comparing the measurements of the child at birth with those of the adult, we find that the base in the adult is 2.81 times, and the side 3.41 times that of the child; in other words, the sides of the triangle increase far more than the base, and its height in the adult (representing very nearly the entire height of the sternum), is 3.78 times that in the new-born child. Consequently, in the course of its transformation the thorax not only descends, but it is also lengthened in the adult, as compared with the form that it had at birth.

B. Dimensions of Thorax in Relation to Stature.—Besides its descent, there is a second transformation of the thorax, in regard to its volumetric relations to the rest of the body. The perimeter of the thorax and the circumference of the head are pretty nearly equal in the new-born child; if anything, the circumference of the thorax is a trifle less than that of the head; but when it equals it, this is a sign of robustness. In the majority of cases it is not until the second year or thereabouts that the two circumferences become equal. If, however, such inequality should still persist after the child had entered upon the third year, it would constitute a sign of rickets (head too large, chest too narrow).

As to the relations between the thoracic circumference and the stature, it is found that in the child at birth the thoracic circumference exceeds one-half the stature by about 10 centimetres. If the difference is less than 8 centimetres it is a sign of feeble constitution, if it is greater than 10 (for instance, 11 centimetres) it is a sign of great robustness.

This difference disappears little by little; at the age of five years it is already reduced to between 4 and 5 centimetres; at the age of fifteen, the period of puberty, it has wholly disappeared, and the well-known relation between the stature and the circumference of the thorax has become established; the thoracic circumference is equal to one-half the stature (see chapter on Form), and this constitutes Goldstein's vital index:

Vi = (100×Tc)/(S)

As early as 1895, Pagliani published some studies of children, which reveal the physiological importance of the dimensions of the thorax; watching the lives of infants whose measurements he took at the foundling asylum, he observed that the mortality of infants is quite rare when they exceed the above proportions between circumference of chest, head, and stature.

From a study of 452 infants, Fraebelius has drawn the following conclusions:

I. Mortality 21 per cent.; circumference of thorax greater than half the stature by 9.10 centimetres; circumference of thorax less by 1.5 centimetres than perimeter of cranium.

II. Mortality 42.9 per cent.; circumference of thorax greater by 7 centimetres than one-half the stature; circumference of thorax less by 2.8 centimetres than circumference of cranium.

III. Mortality 67.5 per cent.; circumference of thorax greater by 4.5 centimetres than one-half the stature; circumference of thorax less by 4.7 centimetres than the cranial circumference.

The thorax in children of five years and upward ought to be larger by a few centimetres (not more than from 4 to 5) than one-half the stature.

C. Transformations of the Thorax Considered by Itself: Alterations in Shape.

Thoracic Index.—Lastly, the thorax changes its shape in the course of growth. In the new-born child it is very prominent in front, and narrow laterally; in the adult, on the contrary, it is more flattened in its antero-posterior dimension and wider transversely. Consequently the transformation consists in a notable difference in the proportion between the width and depth of the chest, that is, between the antero-posterior and the transverse diameters (see chapter on Technique). This proportion constitutes the thoracic index, which is expressed by the following formula:

Ti = (100A-PD)/TD

and this formula gives an idea of the shape of the thorax.

In the child at birth the antero-posterior diameter is very nearly equal to the transverse; accordingly, the index, at birth, oscillates between 90 and 100.

In the adult, however, the thoracic index is on an average 75; the transverse diameter therefore increases much more than the antero-posterior diameter. According to Quétélet, while the transverse diameter multiplies threefold in the course of its growth, the antero-posterior merely doubles (2.36); in addition to this the thorax also lengthens, as we have already seen.

Proportion, Shape and Dimensions of the Thorax.—In the adult normal man we find the following proportions: The distance between the mammary papillæ is about equal to the antero-posterior diameter of the thorax (hence the papillæ indicate the depth of chest) and is also perceptibly equal to one-half the breadth of the shoulders (measured between the two acromia), which, by the way, is the maximum transverse dimension of the skeleton.

This maximum dimension (the biacromial distance) may be regarded as an index of the skeletal development; and Godin takes its proportion to the transverse thoracic diameter (the horizontal distance between the two vertical lines drawn from the arm-pits, in the plane of the mammary papillæ, see Chapter VII, Technique) in order to estimate the proportional relation between the skeleton and the organs of respiration. Since in the course of growth the thorax broadens, that is, the transverse diameter increases more than the antero-posterior, we should expect to find that in the course of evolution, the difference between the transverse development of the skeleton and the lateral development of the thorax steadily diminishes.

It happens, on the contrary, that from the age of ten years onward, during the whole puberal development, the transverse diameter of the thorax steadily becomes less, as compared with the breadth of the shoulders, so much so that if the difference was at first 97 millimetres, it becomes finally 116 millimetres. According to Godin, this indicates that the thorax does not obey the harmonic laws of the development of the skeleton as a whole, but that, owing to causes of adaptation (the school!) it remains definitely inferior to the development which it might have attained, and consequently results in throwing the organism out of its physiological equilibrium. In fact, if we make men raise their arms, especially men of the student class, a certain hollowness, which is æsthetically displeasing, is revealed along the sides of the thorax. This deficiency is corroborated, according to Godin's studies, by his observation of another correspondence in the measurements of the thorax. In addition to the customary measurements, Godin introduced, besides the well-known and classic thoracic perimeter—which is the circumference taken in the horizontal plane passing through the nipples—two other circumferences: one of them higher up, the subaxillary circumference, which includes a large proportion of the pectoral and dorsal muscles; and the other lower down, the submammary circumference, which determines solely the measurement of the thoracic skeleton, since the intercostal muscles are practically the only ones which descend to this level. These two circumferences are to be considered together, according to Godin, as expressing the relation between the organs of respiration and the muscular mass. In complete repose, the subaxillary circumference is much greater than the submammary; but at the moment of maximum inspiration the latter should become equal to the former; hence, the difference between the submammary circumference in repose and during inspiration furnishes an indirect index of the respiratory capacity, and the subaxillary circumference is a test of individual capacity. Godin notes that inspiration almost never succeeds in attaining an equality between the two circumferences.

Shape of the Thorax.—In regard to the shape, which stands in relation to the thoracic index, it is found to vary according to individual types; in fact the index itself, although showing a mean average of 75, oscillates between the extremes of 65 and 85. As a general rule, the brachycephalic races have a deeper thorax, i.e., having a cross-section of more rounded form; the dolichocephalics, on the contrary, have a more flattened thorax in the antero-posterior direction (these races, such as the negroes, are more predisposed to contract pulmonary tuberculosis). Consequently there is a correspondence in type between the head and the thorax. In the measurements taken by me among the women of Latium the results show that the brachycephalics had an average depth of thorax amounting to 188 millimetres and the dolichocephalics only 181 millimetres, while the transverse diameters were very nearly equal: 241 millimetres in the brachycephalics, and 240 millimetres in the dolichocephalics. Hence, the resultant thoracic index of 78 for the brachycephalics and 75 for the dolichocephalics.

Such differences in the index indicate also differences in the formation of the thorax: that it is more or less flattened in the dolichocephalics, and more prominent in the brachycephalics. There is a corresponding diversity of form in the breasts of the women: the dolichocephalic races have more elongated breasts (pear-shaped), the brachycephalics more rounded.

The shape of the thoracic section is at the present time taken into careful consideration, especially in medicine, because it is apt to reveal predispositions to diseases.

It may be obtained by the aid of the cyrtometer (see chapter on Technique). At the present day, however, exceedingly complicated instruments have been constructed, which, by the aid of recording indexes, give a direct representation of the shape of the thoracic perimeter, together with its modifications and respiratory oscillations.

Since these instruments are, for the present, very far removed from widespread practical use, we may adopt as an excellent method for determining the shape and, at the same time, the dimensions of the thorax, that of Maurel, in his research regarding "the square surface of the thoracic section."

Having determined the anthropometric points, Maurel passes strips of metal (stiff enough to retain the shape given them) around the thorax, after the fashion of a tape-measure, first around one half, and then around the other.

Next he places these metal strips (still retaining the shape given them by contact with the thorax), upon a sheet of especially prepared paper, marked in squares, and traces upon it the inner outline of the strips.

The two halves must be made to coincide in such a manner as to reproduce faithfully the thoracic section, both in form and in dimension.

By adding up the squares contained within the outline we obtain the area of the section.

This method is the only really rational method for studying the thorax; and its simplicity, practicality and graphic representation recommend it as a valuable aid to pedagogic anthropology.

There is, for example, an abnormal form of thorax, which I have very often met with in deficient children. It consists in an exaggerated curve of the posterior costal arches, which consequently form a very sharp angle with the vertebral column, which is notably indented, while the sternum is also depressed in a groove, and occupies a plane posterior to that of the ribs. The section of the thorax, in this case, approaches the form of a figure 8; and the thoracic perimeter would not represent the true measurement because it would include the empty spaces left by the front and back depressions. The thoracic index would also give a false idea of the facts, because the antero-posterior diameter would be nowhere so short as at the centres of measurement for this diameter.

The only method for representing the true shape and area of this type of thorax is that employed by Maurel.

Anomalies of Shape.—In addition to the preceding anomaly, very frequent in degenerates, and associated with a deficient development of the lungs and with physical weakness, there are numerous other anomalies. Among others, those that principally deserve attention are the funnel-shaped or consumptive thorax, in which the longitudinal diameter is excessive; the thoracic frame is greatly elongated and the ribs descend to a very low level; this type of thorax is frequent in neuropathic women, and, according to Féré, is associated with degeneration.

The opposite form is the barrel-shaped thorax, in which the prevailing diameter is the antero-posterior; it is very prominent and is frequently met with in persons who are subject to forms of asthma, maladies of the heart, etc.

The bell-shaped thorax is similar to the preceding, but is characterised by an accompanying exceptional brevity of the longitudinal diameter, which causes it to resemble the infantile thorax (arrest of morphological development).

The grooved thorax is the one described above as common among the mentally deficient.

A considerable importance attaches to a form of thorax distinguished by the shortness of the clavicles, in consequence of which the chest remains flat, paralytic or flat thorax (habitus phthisicus). The flattened appearance is due to the fact that the chest cannot rise in front, and the shoulders, being cramped by the shortness of the clavicles, curve forward, while the scapulæ stand out from the plane of the back and spread themselves like wings (scapulæ alatæ). I have met with this form in deficients, accompanied by such laxity of articulations, that it was possible to grasp the points of the shoulders and draw them together until they very nearly met in front.

This form of thorax is characteristically predisposed to pulmonary tuberculosis, and is frequently met with in the macroscelous types.

The commonest deformities of the thorax are those associated with rachitis.

One of the forms regarded as being rachitic in origin is the keel-shaped thorax, in which the sternum is thrust forward and isolated along its median line, like the keel of a boat.

But the thoracic deformities due unquestionably to rickets are of the well-known types that go popularly under the name of hunchback, and are accompanied by curvatures of the vertebral column. The first admonitory symptoms are shown by the so-called rachitic rosary, i.e., by the small swellings due to enlargement of the ends of the ribs at their point of attachment to the sternum. Subsequently, the softened ribs become misshapen in various ways, especially from the fourth rib downward, the upper ribs being fastened and sustained by the thoracic girdle and by the muscles. The curvatures of the vertebral column which accompany rickets are scoliosis or lateral deviation (frequent in school-children) and kyphosis, or deviation in a backward curve; for the most part these two curvatures occur together, so that the vertebral column is thrust outward and at the same time is twisted to one side: kyphoscoliosis.

Pedagogical Considerations.—The following considerations are the natural sequence of what has been said above. Deficiency of the thorax is one of the stigmata left by the school, which in this way tends to make the younger generations feeble and physiologically unbalanced.

The exaggerated importance which is given to the school benches for the purpose of avoiding deformities of the vertebral column deserves to be put aside and forgotten, as an aberration of false hygiene. The bench will not prevent restriction of the thorax; before reaching the critical point which the improved school bench is intended to prevent, many impoverishments of the organism, fatal to robustness and health, and often to life itself (predisposition to tuberculosis!) have been incurred; and there is no other remedy to obviate them than a reform in pedagogic methods. The admonitory fact that neglected, despised, half-starved children have an enormous advantage in the development of the thorax over the more intelligent children who are well-fed and carefully guarded, and solely because the former are free to run the streets, ought to point the direction in which we should look for means of helping the new generations hygienically. They have need of free movement and of air. The recreation rooms which tend to keep the children of the street shut up indoors even during recess are taking from the children of the people the sole advantage that still remained to them. Try to realize that these children are obliged to sleep in dark, crowded environments, and that every night, during the period of sleep, they suffer from such acute poisoning by carbon dioxide that they frequently awaken in the morning with severe pains in the head. The life of the streets is their salvation. We condemn children to death, under the delusion that we are working for their moral good; a perverted human soul may be led back to righteousness; but a consumptive chest can never again become robust. Let those who talk of education and morality and similar themes be sure that they are benefactors and not executioners, and let those who wish to do good seek the light of science.

Curvatures of the vertebral column, such as lordosis and kyphosis, cannot be considered solely in relation to the thorax, but in relation to the pelvis as well, because, especially in lordosis, the lumbar vertebræ are also involved, while the pelvis also suffers a characteristic deformity.

CHAPTER IV
THE PELVIS

Anatomical Note.—The five lumbar, the five sacral and the four coccygeal vertebræ constitute the lumbar and sacro-coccygeal section of the vertebral column.

The sacrum, formed by the union of the five sacral vertebræ, appears in the adult in the form of a bone that narrows rapidly from above downward in a general curve whose convex side is turned inward. The coccyx has the importance of being a real and actual caudal appendage, reduced in man to its simplest anatomical expression. On each side of the sacrum the two ossa innominata or hip-bones are attached, constituting a sort of massive girdle (cintura pelvica), serving as point of attachment for the lower limbs, while at the same time it sustains the entire weight of the body and the abdominal viscera. These two bones are made up of three separate parts: an upper part, very broad and rather thin (the ilium, which constitutes the flank or hip), one in front (the os pubis), and a third behind, quite massive, and shaped like the letter V (the ischium). The two ossa innominata and the os sacrum form the pelvis or pelvic basin, a broad cavity with bony walls that are by no means complete, within which are a portion of the digestive organs and a considerable part of the organs belonging to the genito-urinary system. The pelvis supports the vertebral column and is in turn supported by the lower limbs, in quite marvellous equilibrium.

The maximum sexual differences of the skeleton are in relation to the pelvis; in woman the iliac bones form a far ampler basin; in man, the pelvis is higher and more confined and formed of more solid bones; but it is not broader. But where the difference is most apparent is in the pelvic aperture (see Fig. 127) which divides the pelvis into two parts, the upper or great pelvis and the lower or small pelvis. This aperture has distinguishing marks that differ widely between the sexes; in woman it is rounder, in man it is more elongated from front to back and is narrowed toward the pubis. One of the most important points of measurement in anthropology and in obstetrics is the extreme anterior apex of the superior border of the ilium or crista iliaca antero-superior. The woman in whom this dimension (the bis-iliac) is less than 250 millimetres cannot give birth naturally; similarly the woman who has a prominent os pubis (due to rachitis) will owe the attainment of maternity to the intervention of surgery, and perhaps even of the Cæsarean operation.

There are also many ethnical differences in the pelvis: brachycephalics (the mongolian race) have a broader and shallower pelvis than the dolichocephalics, who, on the contrary, have a deeper and narrower pelvis (the negroes). The same thing is met with, notwithstanding its intermixture, in our own race: blond, brachycephalic women have a wider pelvis than brunette, dolichocephalic women.

Accordingly, cranium, thorax and pelvis correspond in one and the same ethnic type.

The abdomen extends from the arch of the diaphragm to the lower extremity of the pelvis. It contains all the viscera of alimentation: the digestive system together with the glands belonging to it; the liver and pancreas, besides the renal system and, in women, the organs of generation (uterus and ovaries). The diaphragmatic arch, having its convex side uppermost, enters the thoracic frame as far as the first dorsal vertebra. The intestinal mass is more noticeable and prominent in persons having a narrow pelvis; in children, for example, the abdomen is very prominent.

Growth of the Pelvis.—In the skeleton of the new-born child the pelvis differs from that of the adult in two particulars: height and direction. The pelvis is low in the new-born child and higher in the adult. The central axis is more oblique from front to back (in the higher mammals the axis of the pelvis is almost central); in the adult, on the contrary, this axis tends to straighten up, to the point of becoming nearly vertical, in relation, that is, to the erect position of man. Hence in the course of growth the pelvis not only becomes proportionally higher, but it undergoes a rotary movement around the cotyloid axis; this movement has the effect of elevating the pubis and bringing the ischium forward.

The vertebral column rests upon the sacrum, which is the retro-cotyloid portion of the pelvis, and its pressure tends mechanically to straighten the pelvis (see diagram, Fig. 128). This process of straightening has certain limits, and is dependent upon the form of curvature of the vertebral column; if this is exaggerated, as in lordosis, the weight is thrown further forward, almost over the cotyles; consequently, the elevation of the pelvis is not properly accomplished (low pelvis found in lordotics). If, on the contrary, the lumbar curvature is wanting or reversed (kyphosis), the pressure of the column is thrown backward and the straightening up of the pelvis is exaggerated (high pelvis found in kyphotics). Independently of pathological deformities, there are various forms of lumbar curvature in the vertebral column that are normal oscillations, or oscillations acquired through adaptation.

An exaggerated lumbar curvature or saddle-back is found in children accustomed to carry heavy loads upon their shoulders; a diminished curvature is found in children constrained to remain in a sitting posture for many hours a day. The sitting posture tends to cancel the lumbar inward curve; consequently, while children are in school they are promoting the elevation of their pelvis.

The elevation of the pelvis proceeds rapidly at the fifteenth year, during puberty, when the muscular masses become more solid.

A woman is not fitted for motherhood, even if physically developed, so long as her pelvis has not rotated normally. But if the rotation is exaggerated (due to prolonged sitting posture during years of growth), this is very unfavourable to normal childbirth. In rickets, associated with kyphosis, there is a form of exaggerated rotated pelvis (pubis high). The laborious "modern" childbirth, and the dangerous childbirth in the case of women who have devoted much time to study, must be considered in connection with these artificial anomalies. Free movement and gymnastics have for this reason, in the case of women, an importance that extends from the individual to the species.

CHAPTER V
THE LIMBS

The study of the limbs is of great importance, because, although it is the special province of the bust to contain the organs of vegetative life, it is the limbs which render it useful. In fact, it is the lower limbs which control our locomotion and the upper limbs which execute the labour of mankind.

One characteristic of man, equally with that of standing in an erect position, supported only on the lower limbs, is the independence of the upper limbs, which are raised from the ground and relieved of the function of locomotion—a function that still continues in all other mammals, excepting the anthropoid apes, whose upper limbs are extremely long and barely escape the earth, and serve the animal merely as an aid and a support in walking. The birds, although supported on their hind limbs alone, nevertheless have their fore limbs assigned to the sole office of wings for the transportation of their bodies.

Consequently, the free and disposable upper limb, peculiar to mankind, would seem to mark a new function in the biologic scale—human labour.

Anatomy of the Skeleton of the Limbs.—In contrast to the bust, the limbs have an internal skeleton, adapted solely to the function of support (not of protection). The bones are covered with masses of striped muscles, which have as their special function voluntary movement, that is to say, obedience to the brain.

The upper and lower limbs correspond numerically, and the arrangement of the bones is analogous; and this holds true for all the higher vertebrates. The nearest bones, those that are attached to the trunk, are single in all four limbs. Then, just as though branching out, they next double in number, and then multiply successively as we approach the extremities of the limbs. Thus the forearm and the lower leg have two bones, and the hands and feet have many.

In the upper arm we have the humerus, in the thigh the femur, in the forearm the ulna and radius (the ulna is situated on the same side as the little finger and the radius on that of the thumb), in the lower leg the tibia and fibula. Then come the many short bones (eight in the carpus and seven in the tarsus) which in the hand form the wrist or carpus, and in the foot the ankle or instep, the tarsus. These are followed by other long bones (five in the hand and five in the foot), which constitute the metacarpus and metatarsus, and these in turn by the long bones of the phalanges (fingers and toes), which grow successively smaller toward the extremities and are successively named proximal, middle and distal phalanges (phalangettes). These last are missing in the thumb and the big toe. In conjunction with the last phalanges, the fingers and toes are protected by nails.

The Growth of the Limbs.—Recent studies, conducted principally by Godin in France, author of the classic work upon growth, have demonstrated that the long bones of the limbs obey certain special laws of biologic growth.

While a long bone is growing in length it does not grow in width or thickness, and while it is increasing in thickness it does not gain in length; hence the lengthening of the bones takes place in alternate periods; during the period of repose relative to growth in length, the bone gains in thickness.

I have already explained, in connection with the stature, that we owe the growth of the long bones to a variety of formative elements, the cartilages of the epiphyses, which control the growth in length of the long bones, and the enveloping membrane of the body of the bone, the periosteum, which presides over the growth in thickness.

The above mentioned alternation in the growth of the bones must therefore be attributed to an alternation in the action of these various formative elements of the bones.

In the case of two successive long bones (for example, the humerus and radius, the femur and tibia, the metacarpus and phalanges, etc.), they alternate in their growth; while one of them is lengthening, the other is thickening; consequently the growth of a limb in length is not simultaneous in all the bones, but takes place alternately in the successive bones. During the time when the growth devolves upon the longest bone, the limbs show the greatest rate of increase in length, and when, on the contrary, it devolves upon the shortest bone, the growth is less; but in either case it continues to grow.

The growth of the long bones of the limbs proceeds by alternate periods of activity and repose, which succeed each other regularly.

These periods of activity and repose occur inversely in each two successive bones.

The periods of repose from growth in length are utilised for gain in thickness, and reciprocally. The long bones lengthen and thicken alternately, and not simultaneously.

It is only at the age of puberty (fifteenth year) that a complete simultaneity of growth takes place, after which epoch the growth in stature and length of limb diminishes, yielding precedence to that of the vertebral column.

When the complete development of the bodily proportions is attained (eighteenth year), the length of the lower limbs is equal to one-half the stature.

When the upper limbs are extended vertically along the sides of the body, the tip of the middle finger reaches the middle point of the thigh, while the wrist coincides with the ischium (hip-bone). The total spread of the arms is, on an average, equal in length to the stature.

The proportions between the lower limbs and the bust, resulting from the attainment of complete individual development, determine the types of stature: macroscelia and brachyscelia. Since the order of growth as between the two essential portions of stature is now determined, we are able to interpret macroscelia as a phenomenon of infantilism (arrested development of the bust).

Malformations. Excessive Development of the Nearer and Remoter Segments.—But there are other proportions that are of interest to us, within the limbs themselves. Even between the nearer and remoter portions of the limbs there ought to be certain constant relations (indices) that constitute differential characteristics between the various human races and between man and the ape. If the humerus or upper arm is taken as equal to 100, the radius or forearm is equal to 73 in the European, while in the negro it is equal to about 80. Furthermore, it is a well-known fact that excessive length of the forearm is an ape-like characteristic.

Consequently, the measurement of the segments of the limbs is important, and it is made with a special form of calipers; when the index of the segments deviates from the accepted normal figure, this constitutes a serious anomaly, frequently found in degenerates, and it often happens that an excessive development of the remoter segments, the bones of the extremities, explains the excess of the total spread of the arms over the stature, unassociated with the macroscelous type.

Absence of Calf.—In addition to this fundamental deviation from normality, there are other malformations worthy of note that may occur in the limbs. Such, for example, is a deficiency or absence of the calf of the leg. The well-turned leg, which we admire as an element of beauty is a distinctive human trait most conspicuous among the races that we regard as superior. Among the more debased negro races the leg is spindling and without any calf; furthermore, it is well known that monkeys have no calves, and still less do they exist among the lower orders of mammals.

Flat Feet.—Another important malformation relates to the morphology of the feet. Everyone knows the distinctive curve or arch of the foot, and the characteristic imprint which it consequently leaves on the ground. Sometimes, however, this arch is missing, and the sole of the foot is all on the same plane (flat foot). The dark-skinned natives of Australia have flat feet as one of their racial characteristics; in our own race it constitutes an anomaly that is frequent among degenerates. Flat feet may also be acquired as the result of certain employments (butler, door-keeper, etc.), which compel certain individuals to remain much of the time on foot. But in such cases the deformity is accompanied by a pathological condition (neuralgic symptoms and local myalgia). Like all malformations, this may have special importance in connection with infantile hygiene (the position of the pupil, the work done by the children, etc.).

Opposable Big Toe.—Another malformation combined with a functional anomaly, that is never met with as a deformity resulting from adaptation, is the opposable big toe. Sometimes the big toe is greatly developed and slightly curved toward the other toes, and capable of such movement as to give it a slight degree of opposability; hence the foot is prehensile. This characteristic, regularly present in monkeys, is so far developed in certain degenerates as to make it possible for them to perform work with their feet (knitting stockings, picking up objects, etc.); so that this class of degenerates, who are essentially parasites, solve the problem of supporting themselves by trading on the curiosity of the public, so that, by straining a point, we might bestow upon them the title of foot labourers.

Loose and Stiff Joints.—Anomalies may also occur in connection with the articulation of the joints. It sometimes happens that they are extremely loose and weak, and allow the bones an excessive play of movement; and, if the lower limbs are thus affected, it increases the difficulty of maintaining equilibrium when standing erect or walking. On the other hand, it may happen that the articulations are too stiff, and consequently render many movements difficult, especially if through an anomalous development of the outer coating of the bone, it results in congenital ankylosis.

Curvature of the Legs.—A special importance attaches to certain alterations undergone by the heads of the bones which contribute to the formation of the knee, because of the curvature of the leg which results from them (rachitis, paralysis). The leg may become bowed outward or inward; when it is bowed inward (knock-knees, genu valgum), the knees strike together in walking; when, on the contrary, it is bowed outward, the result is bow-legs (genu varum), known popularly in Italy as "legs of Hercules," a deformity which in a mild degree may also result from the practice of horse-back riding.

Club-foot (Talipes).—Other deviations from the normal position occur in connection with the foot. Certain paralytic children (Little's disease) walk on the fore part of the foot (talipes equinus, "horse's foot"); in some cases the foot is also turned inward, and consequently such children cross their legs as they walk (talipes equino-varus).

The Hand

Chiromancy and Physiognomy. The Hand in Figurative Speech. The High and Low Type of Hand.—The hand is in the highest degree a human characteristic. It is man's organ of grasp and of the sense of touch, while in animals these two functions are relegated to the mouth. The hand has always claimed the attention not only of scientists but of all mankind without distinction. Attempts have been made to discover the secrets of human personality from the hand, and a whole art has been built up, called chiromancy, which endeavours to read from the hand man's destiny and psychic personality, just as physiognomy was the art of interpreting the character from the face.

Chiromancy was an accredited art as far back as the days of ancient Greece, and it also had a great vogue in the middle ages; while to-day it is out of date and superseded, or perhaps is destined to rise again in some new form, just as physiognomy has risen again in the study of "expressions" of the face and the imprints which they leave behind them. Scientists also have made the hand the object of their careful consideration; and the result of their researches shows that the hand really does contain individual characteristics that are not only interesting but, up to a certain point, are revelations of personality. A written word, a clasp of the hand, may furnish documents for the study of the individual. Graphology, for instance, is naturally related to the functional action and to the characteristics of the hand itself. Gina Lombroso has recently made a study of the hand-clasp in its relation to character; when a haughty person offers his hand, he has the appearance of wishing to thrust you from him; the miser barely offers the tips of his fingers; the timid man yields a moist and chilly hand to your touch; the loyal friend makes you feel the whole vigor of his hand in its cordial pressure.

In the gesture we have an individual form of linguistic expression. Consequently, man reveals himself, not alone through his creative part, the head, but also through its obedient servant, the hand. "The hand is gesture, gesture is visible speech, speech is the soul, the soul is man, the soul of man is in the hand."

Furthermore, we can judge from the hand whether a man is fitted for work or not; and it is to work that the hand owes its human importance. The first traces of mankind upon earth are not remains of skeletons, but remains of work—the splintered stone. The whole history of social evolution might be called the history of the hand. To say that the hand is the servant of the intelligence is to express the truth in too restricted a way, because the intelligence is nourished and developed through the products of the hand, as by degrees the work of the latter transformed the environment. Hence, the history of our intellectual development, like that of our civilization, is based upon the creative work evolved by the collaboration of hand and head. And so, in the orphan asylums, we have the children sing the hymn to the hand, which is a hymn to labour and to progress:

All the solemn acts of life require the cooperation and sanction of the hand. We take oath with the hand; marriage is performed by uniting the hands of the bridal pair; in proof of friendship or to seal a compact, we clasp hands. The word hand has come to be often used in a symbolic sense in many expressive phrases possessing a social and moral significance: "Take heed that the hand of the Lord does not fall upon you;" "Pilate washed his hands;" "to put oneself into another's hands;" "to have a lavish hand;" "to sit with idle hands" or "with the hands in the pockets;" "one hand washes the other;" "to have a hand in the pie;" "to turn one's hand to something;" "to lend a final hand;" "to speak with the hand on the heart;" "to believe the evidence of one's hands," etc.

And this high and symbolic significance given to the hand dates back even to bible times:

Solomon says: "The length of days is in her right hand; and in her left hand riches and honour" (Prov. 3, 16).

And Moses: "Therefore shall ye lay up these my words in your soul and bind them for a sign upon your hand" (Deut. 11, 18).

Attempts have recently been made to describe the "psychological types" of the human hand. Zimmermann, for instance, studies two types of hand: the high type, delicate, small, slender, with rounded, tapering fingers, and convex nails; a hand which would indicate a fine sensibility, delicate and refined sentiments, a well balanced mind, a high degree of intelligence, a strong and noble character. And there is the low type, coarse, short and stocky, with thick fingers and flat nails; an index of sluggish sensibilities, vulgar sentiments and a low order of intelligence, a weak will and apathetic character.

In accordance with the theories of mechanics, the type of hand has been considered in relation to its organic use and morphological adaptation. In general, the hand used in the coarser forms of work is of the low type; the high type of hand is that required for nimble and fine movements, in which there is need of the successive concurrence of all those delicate little groups of muscles which are able to act independently and thus give to this organ the marvelous and subtle variety of movements which distinguish it. In regard to dimensions, the large, heavy hand would betoken use, and the little hand disuse. Therefore, the small hand may be considered as a stigma of parasitism, a distinction which at the present day has lost its nobility. Excepting in so far as the "brain workers," who make themselves useful without employing their hands, may still show a distinctive smallness of these members.

We should not, however, adhere solely either to the psychological theory of the hand, or to the theory of adaptation; it is necessary to consider the characteristics of the hand from several different points of view.

Dimensions.—The dimensions of the hand bear a constant relation to the stature and to certain partial dimensions of the body, while the various parts of the hand preserve constant reciprocal proportions.

As far back as in the time of Vitruvius it was known that the human hand is related to the stature in the proportion of 10 to 100. This is a very important fact to know, because the proportion varies in the inferior races and in the anthropoid apes, the descent in the scale showing a corresponding increase of length of hand relatively to the stature. Thus, for example, in the Mongolian races the proportional length of the hand is 12.50, and in the higher apes it equals 18. Consequently too long a hand is in itself an anomaly that indicates a low type of man; it is to be classed with those anomalies that were formerly regarded as atavistic reversions, phenomena of absolute retrogression in the biological scale.

Relations between the Hand and the other Dimensions of the Body.—The closed fist, taking the extreme outside measurement between the metacarpophalangeal articulations, corresponds to the breadth of the heart.

The length of the hand corresponds to the height of the visage, and also to the distance intervening between the sternal incisura and the auricular foramen; it is also equal to the distance between the two nipples, and therefore also corresponds to the depth of the chest.

There may be hands which are either excessively large or much too small, and that are really marks of degeneration. An excessive volume of these members is called megalomelia, and an excessive smallness oligomelia.

We may encounter an extremely small hand quite as often in the son of an alcoholic labourer as in the son of a degenerate aristocrat; frequently men whose parents were mentally deficient have small, delicate, almost effeminate hands.

The Proportions between the Various Segments of the Hands.—The length of the middle finger, measured from the digito-palmar plica or fold, ought to equal the length of the palm.

Hence the index of the palm should be the proportion between the length of the palm itself and the length of the middle finger. This proportion is of importance because it has certain human characteristics; as a matter of fact, in the anthropoid apes the metacarpus is much longer than the fingers and the palm has a far lower index than that of man. In degenerates (thieves) the hand is frequently narrow and long.

The Proportions of the Fingers.—If the first and second articulations of the fingers are flexed, leaving the third extended, we find that the extremity of the middle finger reaches to the point where the thenar and hypothenar eminences (fleshy prominences at base of palm) are nearest to each other.

This basic point is only approximate and serves to tell us whether the middle finger is normal. The middle finger serves as a measure for the others, as follows:

• The index-finger reaches to the base of the nail of the middle finger.
• The thumb, to the middle of the first phalanx of the middle finger.
• The ring finger, to the middle of the nail of the middle finger.[47]
• The little finger, to the third articulation of the ring finger.

It often happens that the development of the ulnar side of the hand—the little finger, or both little and ring finger together—is defective. Sometimes the little finger is not only extremely small, but a special malformation renders it shorter still when the hand is open; the second phalanx remains flexed, and cannot be extended. Combined with the shortness of such fingers there is also an extreme slenderness—cubital oligodactylia. It is a far rarer thing to find similar anomalies in the case of the index-finger. The thumb, on the contrary, is sometimes extremely short, in consequence of which it has slight opposability.

Functional Characteristics.—What characterises the functional action of the human hand is the opposability of the thumb. There ought to be a perfect movement of opposability of the thumb in respect to all the other fingers; but many imbecile children accomplish this movement imperfectly. The mobility of the thumb is associated with a group of muscles situated at its base which forms the great tenar eminence of the palm, opposite which, in corresponding relation to the little finger is the small hypothenar eminence. An insufficient development of these palmar eminences represents a serious malformation, which entails functional disturbances. The hand of the monkey is flat.

The Nails.—We have already seen that in the high type of hand the nails should be convex and long, and that in the low type, on the contrary, they are short and flat.

The normal nail should extend to an even level with the fingertip. Manual labour should normally serve the purpose of keeping the nails worn down; but we, who are not hand-labourers, must use the scissors, in order to maintain the normal state.

For, if they were not worn down, the nails would attain an enormous length, like the nails of certain kings of savage tribes, who as a badge of authority have such long nails that their hands are necessarily kept motionless; these kings must in consequence be waited on, even for the smallest need, and actually become the slaves of their own nails, which might be shattered by any sudden movement on the part of their royal possessor. Long nails, therefore, are a sign of idleness, while at the same time they demand a great deal of attention. Accordingly, let us repudiate the fashion of long nails.

As a form of anomaly, we sometimes meet with nails of such exaggerated length that they have the aspect of claws—onychogryposis; or, again, an almost total absence of nails, which are reduced to a narrow transverse strip—this characteristic is often found in idiots, and is aggravated by the fact that from childhood such persons have had the habit of "biting their nails."

Sometimes the nails are exceedingly dense, or actually consist of several superimposed layers, so rich in pigment that they lose their characteristic transparency.

This condition is due to trophic disorders of the nails.

Teratology and Various Anomalies.—There are certain monstrosities that sometimes occur in connection with the hand, such as hexadactylism and polydactylism, or hands with six or more fingers; or else hands with less than five fingers—syndactylism. There may even be a congenital absence of a phalanx, with a consequent notable shortness of the finger—brachydactylism.

Another sort of anomaly frequently found in deficients consists of an excessive development of the interdigital membrane, to the extent of giving the hand the appearance of being web-fingered. An anomaly of minor importance consists in a distortion of the fingers; the little finger has one of its phalanges turned backward. All the fingers ought to be in contact throughout their whole length, and not leave open spaces between them.

Lines of the Palms.—The lines of the palms, which used to be of so much importance in chiromancy, are now taken into consideration even in anthropology, being studied in normal and abnormal man, and also in the hands of monkeys. The lines of the palms are three in number. The one which follows the curve of the tenar eminence is known in chiromancy as the line of life, and, if long, deep and unbroken, was supposed to denote good health and the prospect of a long life; in anthropology it is called the biological line. The second crease, which ought to meet the former between the thumb and the index-finger, is the line of the head, or cephalic line, and in chiromancy its union with the line of life was supposed to denote a well-balanced character.

The line highest up, which begins between the index- and middle finger and extends to the extreme margin of the palm, is the line of the heart or the cardiac line, which in chiromancy is supposed to indicate the emotional development of the individual. These lines taken together form a semblance of the letter M, and are characteristically and gracefully curved. It is considered as an anomaly, to be met with among degenerates and even in mongoloid idiots, to lack any of these lines (numerical reduction) or to have their arrangement distinctly horizontal, and reminiscent of the hand of the monkey.

If we trace backward in the zoological scale, we find as a matter of fact that to begin with, there were no lines in the palms, and then there appeared a single crease high up, such as we still find in the Cebus. In the human hand Carrara has recently made a study of these anomalies, distinguishing several types. In the first type there is a single transverse furrow. In the second type there are two furrows which, however, follow a definitely straight and horizontal direction and consequently are parallel. In a third type a single transverse furrow is associated with a very deep longitudinal furrow running from the carpus to the base of the index- and middle finger—a form that Carrara has found only in criminals. Nevertheless, many idiots exhibit a similar longitudinal furrow, due to a peculiar development of the palmar aponeurosis.