He in whom the muscular or cellular fibres are relaxed, will complain of lassitude, drowsiness, weakness, swellings, his head and stomach remaining unhurt. Another will suffer all the disorders incident to the lungs, who received them from nature not indued with a proper degree of strength. In these the vascular system of the head is weak, they are troubled with incessant head-achs, or bleeding at the nose, to which other studious youths are obnoxious, their intense application to study forcing the blood upwards. Finally, every man, according to the part affected with weakness, is liable to complain of some disorders more than others. Even strength itself has its disadvantages; for whilst robust and vigorous young men devote themselves to study with unbridled ardour, the power of the soul, being rous’d and strongly stimulating the whole system, so increases the action of the solids, that there arise diseases occasion’d by too violent a motion, such as inflammations and malignant fevers; and when these disorders are once begun, they return for some years, till the strength being entirely broken, chronical disorders succeed, according to the common fate of mankind. A great deal depends upon the age, with regard to which we should not be so indiscreet as to bear too hard upon youth, nor exact from them over great tasks; for nothing so totally exhausts and destroys the strength. I have often found boys of a penetrating genius, tinctured with learning beyond what could be expected from their years, and always with some concern, as I saw how it would end; because our youthful days should be consecrated to exercise, and to acquiring strength by its means, and not to severe study, which obstructs both vigour and growth.