Weight
The weight is a measure which should be taken in conjunction with the stature; because, while the stature is a linear index of the development of the body, the weight represents a total measure of its mass; and the two taken together give the most complete expression of the bio-physiological development of the organism.
Furthermore the weight permits us to follow the oscillations of development; it provides educators with an index, a level of excellence, or the reverse, of their methods as educators, and of the hygienic conditions of the school or of the pedagogic methods in use.
The fact is, that if a child is ill, or languid, etc., his stature remains unchanged; it may grow more slowly, or be arrested in growth; but it can never diminish. The weight, on the contrary, can be lost and regained in a short time, in response to the most varied conditions of fatigue, of malnutrition, of illness, of mental anxiety. We might even call it the experimental datum of the excellence of the child's development.
Another advantage which the measure of weight has over that of stature is that it may serve as an exponent of health from the very hour of the child's birth; while stature does not exist in the new-born child, and begins to be formed (according to the definition given) only after the first year of its life, that is, when the child has acquired an erect position and the ability to walk steadily.
Variations.—Weight is one of the measures that have been most thoroughly studied, because it is not a fruit of the recently founded science of pedagogic anthropology; but it enters into the practice of pediatricians (specialists in children's diseases) and of obstetricians (specialists in childbirth), while even the general practitioner can offer precious contributions from his experience.
According to Winckel, and practically all pediatricians agree with him, "the weight of a child, if taken regularly, is the best thermometer of its health; it easily expresses in terms of figures what the nursing child cannot express in words."[34]
The new-born child weighs from three to four kilograms; but oscillations in weight from 2,500 to 5,000 grams are considered normal. Some obstetricians have noted weights in new-born children that are enormous, true gigantism, which, however, while possible, are altogether exceptional; nine and even eleven kilograms.
The oscillations in weight of the child at birth, within normal limits, may have been determined by general biological factors, as for example the sex (the female child weighing less than the male), and the race (especially in regard to the stature of the parents): but the factors which influence the weight of the new-born child in a decisive manner are those regarding the hygiene of generation.
1. "The children which have the greater weight are those born of mothers between the ages of twenty-five and thirty." (Mathews Duncan.) Let us recall what we have said regarding stature; at the end of the twenty-fifth year, that is, at the end of the period of growth, man is admirably ripe for the function of reproduction; and we ought further to recall the views cited regarding the mortality of children conceived at this age which is so favourable to parenthood; and finally the note in regard to celebrated men, almost always begotten at this age.
2. "First-born children have in general a weight inferior to that of those born later (1,729 first-born children gave an average of 3,254 grams: while 1,727 born of the second or subsequent conceptions gave an average of 3,412 gr.)" (Ingerslevs). Let us remember that celebrated men are scarcely ever the first-born.
3. "Very short intervals between successive pregnancies interfere with this progression in weight; long intervals on the contrary do not interfere with it" (Wernicke). In other words, too frequent pregnancy is unfavourable to the result of the conception.
4. "Mothers who, at the birth of their first child weigh less than fifty-five kilograms and are under twenty years of age, have children of inferior weight, who are less predisposed to normal growth" (Schafer).
Let us recall what we have said regarding the form and the scanty weight in the case of macrosceles; and also in regard to the age of procreation in its relation to stature.
5. "Women who toil at wearisome work up to the final hour give birth to children inferior in weight to those born of mothers who have given themselves up to rest and quiet for some time before the expected birth" (Pinard).
All these considerations which refer to normal individuals, represent a series of hygienic laws regarding maternity, which may be summed up as follows: excellence in procreation belongs to those mothers who have already attained the age at which the individual organism has completed its development, and before it has entered upon its involutive period; the mother must herself have a normal weight; the pregnancies must be separated by long intervals; and during the last weeks of pregnancy it is necessary that the mother should have the opportunity of complete rest.
The increase in weight of the new-born child during the first days of its life, may constitute a valuable prognostic of the child's life. That is to say, through its successive gains it reveals the vitality, the state of health of this new human being.
Here also the pediatrists can furnish us with valuable experimental data, which serve to formulate the "laws of growth." These are:
1. From the moment of a child's birth, throughout the first two days, it suffers a loss in weight of about 200 grams, due to various causes, such as the emission of substances accumulated in the intestines during the intrauterine life (meconium), and the difficulties of adaptation to a new environment and to nutrition. But by the end of the first week a normal child should have regained its original weight; so that after the seventh day the normal child weighs the same as at the moment of birth.
On the contrary, children born prematurely, or those having at the time of birth a weight below the average, or those that are affected with latent syphilis, or are weak from any other cause whatever, regain their original weight only by the end of the second week.
Accordingly, in one or two weeks the family may form a prognosis regarding future life of the new-born child: a matter of fundamental and evident importance.
Furthermore, an antecedent detail of this sort may be valuable in the progressive history of subjects who, having attained the age for attendance at school, come to be passed upon by the teachers.
To this end, in the more progressive countries, the carnet maternel, or mother's note-book, has begun to come into fashion, for the use of mothers belonging to the upper social classes (as, for instance, in England): it consists of a book of suitable design, in the form of an album, and more or less de luxe in quality, in which the most minute notes are to be registered regarding the lives of the children from the moment of their birth onward. Various authors, especially in France, now give models for the maternal registration of the child's physiological progress; true biographic volumes that would form a precious supplement to the biographic charts of the schools: and the efforts of the family would round out and complete those of the school for the protection of the lives of the new generations. Such assistance, however, is only an ideal, because nothing short of a great and far distant social progress could place all mothers (the working women, and the illiterate of Italy) in a position to compile their carnet maternel. Auvard advocates, for registering the weight of the child during the first days of its life, a table in which the successive days from the first to the forty-fifth are marked along a horizontal line, while a vertical column gives a series of weights, with 25-gram intervals, covering a range of 700 grams, the multiples of a hundred being left blank, to be determined by the actual weight of the child and filled in by the mother or whoever takes her place.
Fig. 36.
In such a table, the graphic sign indicating the changes in weight ought to fall rapidly and rise again to the point of departure by the seventh day, if the child is robust.
Another law of growth which may serve as a prognostic document in the child's physiological history is the following:
2. "Children nourished at their mother's breast double their weight at the fifth month and triple it at the twelfth." In other words, before the middle of its first year a healthy child, normally nourished, will have doubled its weight.
On the contrary, "Artificial feeding retards this doubling of weight in children, which is attained only by the end of the first year; so that the weight is not tripled until some time in the course of the second year."
And this gives us pretty safe principles on which to judge of the personality in the course of formation, at an epoch when stature does not yet exist.
Undoubtedly a great moral and social progress would be accomplished through a wide dissemination of very simple and economical carnets maternels; which should contain not only tables designed to facilitate the keeping of the required records, but also a statement of the laws of infant hygiene; or at least, simple and clear explanations of the significance of such phenomena, in relation to the life and health of the child; and also as to the causes which produce weakness in new-born children; or in other words, advice regarding the fundamental laws of the hygiene of generation. All that would be needed, in such case, would be a progressive exposition by means of the carnets, through lessons made as simple and as objective as possible, such as the weighing of small babies, to make the much desired "education of the mothers" both possible and practical.
But without this practical means; without this new sort of syllabarium on hand, to serve as a constant and luminous guide for married women, I do not believe that we shall have much success with the scattered lectures, obscure and soon forgotten, that at present are being multiplied in an attempt to reach the mothers of the lower classes.
In conclusion, I note this last contribution that comes to us from the pediatrists:
3. "There are certain maladies that cause a daily and very notable loss in weight"; they are the intestinal maladies; there may be an average loss of from 180 to 200 grams a day; but even in cases of simple loss of appetite (dyspepsia) the weight may decrease by about 35 grams a day. But when a child suffering from acute febrile intestinal trouble (cholera infantum), loses a tenth of his weight in twenty-four hours, the illness is mortal.
Now from the point of view of the educator this fact ought to be of serious interest, because we very frequently find among the recorded details of sickly children, or those suffering from arrested or retarded development, a mention of some intestinal malady incurred in early infancy.
Still one further observation: Meunier has noted a fact of extreme importance: that while children are passing through the period of incubation of an infectious disease, and before they show any symptoms likely to cause a suspicion of the latent illness, they sustain a daily loss in weight, from the fourth or fifth day after exposure to contagion until the appearance of decisive symptoms. In children between one and four years old, the daily loss is about fifty grams, and the total about 300; but such a loss may rise as high as 700 gr. The most numerous observations were taken in cases of measles.
Now, there is no need of explaining the prophylactic importance of observations such as these! A child who for a period of twenty days is in a state of incubation, is called upon to struggle, with all the forces of immunity that his organism possesses, against a cause of disease which has already invaded him; yet no external sign betrays this state of physical conflict. Consequently, the child's organism continues to sustain the customary loss of energy due to the activities of its daily life, and by doing so lessens its own powers of immunity. To prescribe rest, if nothing more, for a child suspected of passing through the period of incubation would in many cases mean the saving of a life, and at the same time would protect his companions from infection, which is communicable even during the period of incubation.
In our biographic records of defective children, which include the great majority of the weakly ones, we find in many cases a characteristic tendency to relapses in all kinds of infective diseases, from which they regularly recovered. Such organisms, feeble by predisposition, yet sufficiently strong to recover from a long series of illnesses, were exhausted in respect to those biological forces on which the normal growth of the individual depends, by this sort of internal struggle between the organic tissues and the invading microbes. No scheme of special hygiene for children of this type can help us, either in the home or at school; the daily variations in weight, on the contrary, might constitute a valuable guide for the protection of such feeble organisms; at the first signs of a diminution in weight, such children ought to be subjected to absolute repose.
The use of the weighing-machine, both at home and in school cannot be too strongly recommended. In America the pedagogic custom has already been established of recording the weight of the pupils regularly once a month; but instead of once a month, the weight ought to be taken every day. The children might be taught to take their own weight by means of self-registering scales, and to compare it with that of the preceding day, thus learning to keep watch of themselves: and this would constitute both a physical exercise and an exercise in practical living.
The weight may be considered by itself, as a measurement of the body; and it may be considered in its relation to comparative mean measurements given by the authorities; just as it may also be considered, in the case of the individual, in its relation to the stature.
a. The weight, taken by itself, is not a homogeneous or rigorously scientific measurement. In the same manner as the stature, it represents a sum of parts differing from one another, the difference in this instance being that of specific gravity. As a matter of fact, it makes a great difference whether a large proportion of the weight of an individual is adipose tissue, or brain, or striped muscles. Each of the various organs has its own special specific gravity, as appears from the following table:
| Specific Gravity | ||
|---|---|---|
| Tubular bones | 1.93 | |
| Spongy bones | 1.24 | |
| Cartilage | 1.10 | |
| Muscles | from | 1.10 |
| to | 1.30 | |
| Tendons | 1.16 | |
| Epidermis | from | 1.10 |
| to | 1.19 | |
| Hair | from | 1.28 |
| to | 1.34 | |
| Liver | 1.07 | |
| Kidneys | 1.04 | |
| Brain | 1.039 | |
| Cerebrum | 1.036 | |
| Cerebellum | 1.032 | |
| Adipose tissue | 0.97 | |
All these specific gravities are low; we weigh but little more than water; and for that reason it is easy for us to swim. But because of the difference in their composition, the total weight of the body gives us no idea of its constituent parts.
Take for example the question of increase in weight. We can compare the mean figures given by the authorities with the ascertained weight of some particular child of a given age, so as to keep an empirical check upon the normality of its growth. But since we know that an individual in the course of evolution undergoes profound alterations in the volumetric proportions of the different organs in respect to one another, we cannot obtain from the total weight any light upon this extremely important alteration in proportions. Thus, for example, Quétélet gives the following figures of increase in weight for the two sexes:
| Weight | Weight | ||||
|---|---|---|---|---|---|
| Age | Males | Females | Age | Males | Females |
| 0 | 3.20 | 2.91 | 15 | 46.41 | 41.30 |
| 1 | 10.0 | 9.30 | 16 | 53.39 | 44.44 |
| 2 | 12.0 | 11.40 | 17 | 57.40 | 49.08 |
| 3 | 13.21 | 12.45 | 18 | 61.26 | 53.10 |
| 4 | 15.07 | 14.18 | 19 | 63.32 | — |
| 5 | 16.70 | 15.50 | 20 | 65.0 | 54.46 |
| 6 | 18.04 | 16.74 | — | — | — |
| 7 | 20.16 | 18.45 | 25 | 68.29 | 55.08 |
| 8 | 22.26 | 19.82 | 30 | 68.90 | 55.14 |
| 9 | 24.09 | 22.44 | 40 | 68.81 | 56.65 |
| 10 | 26.12 | 24.24 | 50 | 67.45 | 58.45 |
| 11 | 27.85 | 26.25 | 60 | 65.50 | 56.73 |
| 12 | 31.0 | 30.54 | 70 | 63.03 | 53.72 |
| 13 | 35.32 | 34.65 | 80 | 61.22 | 51.52 |
| 14 | 40.50 | 38.10 | — | — | — |
INCREASE IN WEIGHT OF BODY
According To Sutils
| Age | Weight of body in grams | Increase |
|---|---|---|
| At birth | 3000 | — |
| 1 month | 3750 | 750 |
| 2 months | 4450 | 700 |
| 3 months | 5100 | 650 |
| 4 months | 5700 | 600 |
| 5 months | 6250 | 550 |
| 6 months | 6750 | 500 |
| 7 months | 7200 | 450 |
| 8 months | 7600 | 400 |
| 9 months | 8000 | 400 |
| 10 months | 8350 | 350 |
| 11 months | 8700 | 350 |
| 12 months | 9000 | 300 |
But these figures give no idea of the laws of growth that govern each separate organ, and that have been studied by Vierordt. According to this authority, the total weight of the body increases nineteen-fold from birth to complete development. Certain ductless glands, on the contrary, diminish in weight in the course of growth; the thymus, for instance, is reduced to half what it weighed originally.
Furthermore, the various organs all differ in such varying degrees, as compared with their respective weights at birth, that it facilitates comparison to reduce the weight of each separate organ to a scale of 1. On this basis we find that when complete development is attained, the eyes weigh 1.7; the brain 3.7; the medulla oblongata (spinal marrow) 7; the liver 13; the heart 15; the spleen 18; the intestines, stomach and lungs 20; the skeleton 26; the system of striped muscles 48.
And these widely different augmentations are not uniform in their progress, nor is the complete development of each organ attained at the same epoch. As a matter of fact, the brain acquires one-half its final weight at the end of the first year of age; the organs of vegetative life attain half their weight at the beginning of the period preceding puberty (eleventh year). To offset the lack of indications regarding such increases in weight, we have a guide in the morphology of growth, which reveals how differently the various parts of the body develop.
However empirical it may be from an analytical point of view, the datum of weight is a valuable index, and represents, taken by itself, a synthetic anthropological measure of prime importance.
It obeys certain laws of growth which are themselves of great interest; namely, there exist two periods of rapid growth: at birth and during puberty; while at various periods in childhood, between the ages of three and nine, there are alternations of greater and lesser growth analogous to those already noted in relation to stature.
Accordingly, the weight confirms the fact that the organism does not proceed uniformly in its evolution, but passes through crises of development during which the forces of the organism are all devoted to its rapid transformation; such periods represent epochs at which the organism is more predisposed to maladies, more subject to mortality and less capable of performing work (compare the observations already made in relation to stature).
Index of Weight.—Accordingly, weight and stature stand in a certain mutual relationship, but the correspondence between them is not perfect. In the study of individual physiological development it is necessary to know the anthropological relation between weight and stature; in other words, the ponderal index. Without this, we cannot get a true idea of the weight of an individual. For instance, if two persons have the same weight, 65 kilograms for example, and one of them has a stature of 1.85 metres and the other of 1.55 m.; it is evident that the first of these two will be very thin, because his weight is insufficient, while the second, on the contrary, will have an excessive weight.
A stout, robust child will weigh less, in an absolute sense, than an adult man who is extremely thin and emaciated; but relatively to the mass of his body, he will weigh more. Now this relative weight or index of weight, the ponderal index, gives us precisely this idea of relative embonpoint, of the more or less flourishing state of nutrition that any given individual is enjoying. Hence it is a relation of great physiological importance, especially when we are dealing with children.
The calculation of the ponderal index ought to be analogous to that of other indexes; what has to be found is its relation to the stature reduced to a scale of 100. In this case, however, we find ourselves facing a mathematical difficulty, because volumetric measurements are not comparable to linear measurements. Consequently it is necessary to reduce the measurement of weight by extracting its cube root, and to establish the following equation:
St:∛(W) = 100:X
whence
Pi = 100(∛(W))/S
The application of this formula necessitates a troublesomely complicated calculation, which it would be impracticable to work out in the case of a large number of subjects. But as it happens, tables of calculations in relation to the ponderal index already exist, thanks to the labours of Livi[35] and it remains only to consult them, as one would a table of logarithms, by finding the figure corresponding to the required stature, as indicated above in the horizontal line, and the weight as indicated in the vertical column.
Some authors have thought that they were greatly simplifying the relation between weight and stature by calculating the proportional weight of a single centimetre of stature and assuming that they had thus reduced the relation itself to a ratio based upon a single linear measurement (one centimetre), analogous to the ratio established by the reduction of the total stature to a scale of 100. But evidently such a calculation is based upon two fundamental errors, namely: first, no comparison is ever possible between a linear measure and a measure of volume; and secondly, the relation which we are trying to determine is that between synthetic measurements, i.e., measurements of the whole, and not of parts.
Fig. 37.
In the aforesaid method of computing (which is accepted by such weighty authorities as Godin and Niceforo), the number expressing the weight in grams is divided by the stature expressed in centimetres, and the quotient gives the average weight of one centimetre of stature expressed in grams. This method, which sounds plausible, may easily be proved to be fallacious, by the following illustration, given by Livi in his treatise already cited (Fig. 37). The two rectangles A and B represent longitudinal sections of two cylinders, which are supposed to represent respectively (in A) the body of a child so fat that he is as broad as he is long (the rectangle A is very nearly square), and (in B) that of a man of tall stature and so extremely thin that he very slightly surpasses the child in the dimensions of width and thickness (note the length and narrowness of rectangle B). Evidently the ponderal index of A is very high and that of B is very low. But if we calculate the proportional weight of one centimetre of stature, it will always be greater in the man than in the child, and consequently we obtain a relation contrary to that of the ponderal index.
Let us make still another counterproof by means of figures; let us take an adult with a stature of 1.70 metres and a weight of 19 kilograms; and a three-year-old child 0.90 m. tall and weighing 55 kg. (the normal weight of a child of four). In the case of the adult one centimetre of stature will weigh 65000/170 grams = 382 grams; while one centimetre of the child's height will weigh 15000/90 = 166 grams. In other words, one average centimetre of the child's stature weighs less than one centimetre of the adult, as it naturally should, while the ponderal index on the contrary is 23.6 in the case of the adult, and 27.4 in that of the child.
The reciprocal relations between stature and weight vary from year to year. In babyhood, the child is so plump that the fat forms the familiar dimpled "chubbiness," and Bichat's adipose "fat-pads" give the characteristic rotundity to the childish face; while the adult is much more slender. A new-born syphilitic child which, with a normal length of 50 centimetres, weighed only two kg.—and consequently would be extremely thin—would have the same identical ponderal index as an adult who, with a stature of 1.65 m., weighed 100 kg.
The evolution of the ponderal index forms a very essential part in the transformations of growth; and it shows interesting characteristics in relation to the different epochs in the life of the individual.
In this connection, Livi gives the following figures, for males and for females; from which it appears that at some periods of life we are stouter, and at others more slender; and that men and women do not have the same proportional relation between mass and stature.
| Indices | Indices | ||||
|---|---|---|---|---|---|
| Age in years | Males | Females | Age in years | Males | Females |
| 0 | 29.7 | 29.6 | 15 | 23.1 | 23.4 |
| 1 | 30.9 | 30.5 | 16 | 23.4 | 23.6 |
| 2 | 28.7 | 28.9 | 17 | 23.1 | 23.7 |
| 3 | 27.5 | 27.3 | 18 | 23.2 | 24.1 |
| 4 | 26.5 | 26.6 | 19 | 23.4 | 24.1 |
| 5 | 25.8 | 25.6 | 20 | 23.5 | 24.1 |
| 6 | 25.1 | 24.8 | — | — | — |
| 7 | 24.4 | 24.1 | 25 | 23.7 | 24.1 |
| 8 | 24.0 | 23.8 | 30 | 23.8 | 24.1 |
| 9 | 23.5 | 23.5 | 40 | 23.9 | 24.7 |
| 10 | 23.1 | 23.2 | 50 | 24.3 | 25.3 |
| 11 | 22.8 | 23.3 | 60 | 24.6 | 25.3 |
| 12 | 23.1 | 23.6 | 70 | 24.5 | 24.9 |
| 13 | 23.4 | 23.5 | 80 | 24.4 | 24.7 |
| 14 | 23.1 | 23.3 | — | — | — |
It may be said in general, so far as regards the age, that the following is the established law of individual evolution: during the first year the ponderal index increases, after which it diminishes up to the period immediately preceding puberty (eleventh year for males, tenth year for females), the period at which boys and girls are exceedingly slender. After this, throughout the entire period of puberty, the ponderal index seems to remain remarkably constant, oscillating around a fixed figure. At the close of this period (seventeenth year for males, fourteenth for females), the ponderal index resumes its upward course (corresponding to the period in which the transverse dimensions of the skeleton increase, and in which the individual, as the phrase goes, fills out), and it continues to rise well into mature life (the individual takes on flesh); until in old age, the ponderal index begins to fall again (the soft tissues shrink, the cartilages ossify, the whole person is shrunken and wasted.)
Fig. 38.
Women, during their younger years are on a par with men in respect to the ponderal index, but in later life surpass them, because of woman's greater tendency toward embonpoint, since she is naturally stouter and plumper than man, who is correspondingly leaner and more wiry.
The following diagram indicates the progressive evolution and involution of the ponderal index throughout the successive stages of life:
The ponderal index has revealed certain physiological conditions in pupils that are extremely interesting. Some authors had already noted that the ponderal index was higher in well-nourished children (Binet, Niceforo, Montessori); but last year one of my own students, Signorina Massa, in a noteworthy study of children, all taken from the same social class and quite poor, and who did not attend the school refectory or have the advantage of any other physiological assistance, established the fact that the more studious children, the prize winners, have a lower ponderal index and a muscular force inferior to that of the non-studious (negligent) pupils. That the development of the ponderal index stands in some relation to the muscular force, might already have been deduced from the fact that the greatest increase of weight is due, in the evolution of the individual, to the system of striped muscles. Studious children, accordingly, are sufferers from denutrition through cerebral consumption; furthermore, they are weakened throughout their whole organism; in fact, I discovered, in the course of researches made among the pupils in the elementary schools of Rome, that the studious children, those who received prizes, had a scantier chest measurement than the non-studious. This goes to prove that school prizes are given at the cost of a useless holocaust of the physiological forces of the younger generations!
That the ponderal index has an eminently physiological significance, is further shown by the following comparative figures between normal and weak-minded children. The stature, which is biologically significant, is lower in the weak-minded; but their ponderal index is greater when they are well fed, as in the asylums in Paris.
Accordingly, the sole cause of the physical inferiority of studious children is study, cerebral fatigue.
BIO-PHYSIOLOGICAL DIFFERENCES BETWEEN NORMAL AND WEAK-MINDED CHILDREN
(Simon and Montessori: Based on Children from 9 to 11)
| Age | Weight in kilograms | Average stature | Ponderal index | |||
|---|---|---|---|---|---|---|
| Weak-minded | Normal | Weak-minded | Normal | Weak-minded | Normal | |
| 9 | 21.0 | 25.5 | 1.15 | 1.24 | 24 | 23.9 |
| 10 | 26.5 | 28.5 | 1.25 | 1.30 | 24 | 23.6 |
| 11 | 27.0 | 30.5 | 1.25 | 1.33 | 24 | 23.6 |
It should be noted that in the foregoing table the normal children include both the studious and the non-studious.