But what is the teaching of physiology on this matter? Through one of its greatest writers, thus it speaks: "If young children are compelled to sit quietly while their minds are urged to undue action, _we take from them the noblest part of their strength, and consume it in the function of thinking_. Thus growth is retarded, the limbs imperfectly developed, the digestion (and thus the blood) becomes bad, scrofula perhaps appears, and then ensues a great predominance of the nervous system. Any _unequal_ development of our faculties is injurious. It is certain that _mental exertions_ weaken the more they are unaccompanied by bodily movements. Those who, _between_ mental occupations, take bodily exercise, can _do more_ than those who neglect this exercise." The grand evils of our present modes of education are, not that too much intellectual training is bestowed, but that physical, social, and domestic training are neglected. The result is a _universal decay of national vigor and health_. Other causes, such as the use of stoves and unventilated houses, improper diet and dress, with excess in other modes of stimulating, have had a large share in the evil, but there can be no doubt that mistaken modes of education are the chief causes of the acknowledged fact that our national health is perishing at a frightful rate. There are facts that prove the Anglo-Saxon race, as developed in America under the best circumstances, is the most perfect race on earth as it respects size, strength, and beauty. The mountain regions of Kentucky and Tennessee, where the climate allows all to live in pure air night and day, with the simple food and habit of forest life, send out sons that, appearing in foreign lands, are followed by admiring crowds as specimen giants. General Washington's staff, though not picked men, were most of them over six feet in height, with size and muscle to correspond. The vigorous mothers and stalwart sons that achieved our Revolution have given place to sickly mothers with a delicate and puny offspring. The Greeks, though they educated the mind, took even more pains to train the body, and thus they became the wisest, strongest, and most powerful people on earth. We might do the same, and with far greater facilities; but, should our present rate of deterioration proceed, two or more generations would bring us out a race of deformed and unhealthy pigmies. For facts to sustain such a prediction, the author begs leave to refer to her _Letters to the People on Health and Happiness_.