This increase in the activity of the nutritive powers during puberty, is not shown simply by the increase of the substance of the body, it manifests itself by other symptoms. More heat is generated in the tissues, as is indicated particularly by the facility with which individuals at the age of puberty resist cold, and by the interesting remark of Quetelet and Smitz, that the summer of all seasons of the year is most fatal to them. Ailments of every kind too show in most subjects, that the influence of the genital organs on all parts of the body may be so great as even to derange the functions: of this character are pains, heaviness in the head, vertigos, redness of the face, numbness in the limbs, dulness and oppression, palpitations of the heart, bleeding from the nose, painful engorgements of the lymphatic ganglions, different inflammations, &c. &c. Finally the body responds like an echo, to all that takes place in the genital system. Need we say that nothing of the kind takes place in eunuchs. The active development of the genital parts exercises an equal influence on the functions of the life of relation, in the faculties of sensation, action, and thought. These faculties, which are so feeble in the eunuch are extremely active during puberty. This is the age of muscular activity and agility. If those who are growing up, sometimes are reluctant to take exercise, this feeling of reluctance depends on a hyperemia of the nervous centres, which soon disappears. Numerous different and generally transient sensations, denote the part which the nervous system takes in what passes in the genital system; and this is proved also by the frequency of convulsive and spasmodic affections at this period of life. The moral susceptibility is then still more exalted than the physical susceptibility. The mind directed and controlled by the most vivid, most varied, and most transient impressions, takes up and lays aside the most opposite opinions, and adopts the most hazardous enterprises. This disposition has existed to so great a degree as even to constitute a kind of monomania, so transient as to be almost imperceptible, and during which crimes, (particularly that of arson) were committed. This fact rests on the authority of Osiander, Henke, of the faculty of medicine at Leipsick, of Marc and of many other authors. (_See Marc’s memoir on incendiary monomania, Annales d’hyg._ October, 1833.) But the mental state resulting from the change of puberty is characterized particularly by the readiness with which one shares the affections of others, partakes of their sympathies, and sympathizes with them. This is the moment of generous ideas, or as is remarked by those, whose minds no longer feel the action of organs which have become mute, the period of illusions. How much experience ought not the mind to gain when passing through this moral tempest? Is it astonishing then to find weak minds and cold