It should be noted that the cold climate of Turin retards puberty (see below): but the above table clearly shows the precocious puberty of young women in easy circumstances; in the great majority, in fact, it occurs between the ages of twelve and fourteen, with thirteen for the average; on the other hand, the majority for reformed prostitutes is between fourteen and sixteen, with fifteen for the average.
Besides labour and nutrition, there are other factors that contribute to the development of stature (which we regard as an index to the entire mass of the body). Such factors are:
Physical Conditions—Heat, Light, Electricity
Thermic Conditions.—Among the physical conditions which may have an influence upon the stature, the thermic conditions ought to receive first consideration.
It is a principle demonstrated by nature that organisms in the course of evolution have need of heat. Even the invertebrates, as for example the insects, develop during the heat of summer; and the eggs of the higher vertebrates such as the birds, develop their embryo by means of the maternal warmth. In placental animals the development throughout the whole embryonic period takes place within the maternal womb, in the full tide of animal heat. In order to preserve life in premature babies, that is, in those born before the expiration of the physiological term of nine months, incubators have been constructed, an oven-like arrangement in which the child may be maintained at a temperature considerably higher than would be possible in the outside air; the term is also specifically used of the structures in which fertilised hens' eggs are kept during the required period of time until the chickens are hatched.
Accordingly it is a principle taught us by nature that organisms in the course of evolution have need of heat. The most luxuriant vegetation, the most gigantic animals, the most variegated birds belong to the fauna and flora of the tropics.
How is this physiological law, which nature expresses in such broad, general lines, to be interpreted by us in the environment of the school? It is well known that in this regard there are two conflicting opinions. There are some who would go to excessive lengths in protecting small children from the cold, by dressing them entirely in woolen garments and keeping their apartments well heated; others on the contrary assert that the physiological struggle of adaptation to the cold invigorates the infant organism, and they advise that the child's body should never be completely protected, as for example that the legs should always be left bare, that the child should be lightly clad, that his apartments should not be heated, etc.
Furthermore, it used to be held in the pietistic schools, and still is to some extent, that warmth had a demoralising influence, inasmuch as it tended to enervate both mind and body.
We educators cannot fail to be interested in such a discussion. As often happens in physiological arguments, the two opposite contentions each contain a part of the truth. In order to get at the truth of the matter, it is necessary to distinguish two widely separated facts: on the one hand, physiological exercise in the form of thermal gymnastics, and on the other, the development of organisms in a constantly cold environment.