Chapter I: Certain Principles of General Biology (7)

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 | Males | Females | Age in | Males | Females
years | | | years | |
-------+-------+---------+--------+-------+--------
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.)

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)

----------------------------------------------------------------------
| Weight in kilograms| Average stature | Ponderal index
|--------------------+--------------------+-------------------
Age |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.

FOOTNOTES:

[4] See further, as to these fundamental ideas: Laloy, _L'Évolution de la Vie. Petite Encyclopédie_ _du XX Siècle_; CLAUDE BERNARD, _Leçons sur les Phènomènes de la Vie_; LE DENTU, in _La Matière Vivante, et Théorie nouvelle de la Vie_; Luciani, _Fisiologia Umana_, in the first chapter: "Material Substratum of Vital Phenomena."

[5] Consult: HAECKEL, _Anthropogenie_; E. PERRIER, _Les Colonies animales et la Formation_ _des Organismes_; RICHET, _L'Effort vers la Vie, et la Théorie des Causes finales_.

[6] CORRENS: _Concerning the Laws of Heredity_.

[7] Translator's note.

[8] Translator's note.

[9] De Giovanni, _Op. cit._, p. 236. Cases referring to the first morphologic combination.

[10] DE GIOVANNI, _Op. cit._

[11] DE GIOVANNI, _Op. cit._

[12] Boxich, _Contribution to the Morphological, Clinical and Anthropological Study of_ _delinquents_.

[13] DENIKER, _Races et peuples de la terre_.

[14] TOPINARD, _Elementi di Antropologia_.

[15] QUÉTÉLET, _Proporzioni medie (mean Proportions)_.

[16] LIVI, _Antropometria Militare (Military Anthropometry)_.

[17] MONTESSORI, _Caratteri fisici delle giovani donne del Lazio._

[18] Translator's note.

[19] Fig. 25 and those following it, dealing with deformities resulting from labour, are taken from Pieraccini's great work, _The Pathology of Labour_.

[20] PIERACCINI, _Op. cit._

[21] ALFREDO NICEFORO, _Les classes pauvres_ (the poorer classes).

[22] Taken from Livi: _On the Development of the Body in relation to the profession and the_ _social condition._ Rome, Voghera, 1897.

[23] MARRO, _Puberty_.

[24] Cited by PAGLIANI, _Human Development, according to age, sex, etc._

[25] RACIBORSKI, cited by MARRO, _Puberty_.

[26] _Idem._

[27] Rousseau, _Émile_, cited by MARRO.

[28] It should be noted that sexual precocity or vice retards the development of puberty, while healthful psychic stimuli are favourable to it. Hence it was a right instinct that led us to give the name of sin and vice to what retards the normal development of life, and virtue and honour to what is favourable to it.--Author's note.

[29] Compare _The method of Scientific Pedagogy applied to infantile education_ _in the "Children's Houses,"_ MONTESSORI: Casa Editr. Lapi, 1909.

[30] MOIGE, _Nouvelle Iconographie de la Salpétrière_, 1894.

[31] APERT, _Op. cit._

[32] Cited by Marro.

[33] Cited by Figueira, _Semejotica Infantile_, p. 121.

[34] Cited by FIGUEIRA (Rio Janeiro) in his volume, _Elementi di Semejotica infantile_, 1906. From this volume, which contains the result of the most modern investigations in pediatry, I have taken a number of data regarding the weight of children.

[35] LIVI: _Antropometria_.