The infant in the nursery, as we have already seen, needs no covering of the kind. It is absolutely necessary that the head should be kept as cool as possible; and absolutely dangerous to cover it too warmly. At a later period, however, the danger greatly diminishes, because the circulation of the blood becomes more equal, and does not tend so much towards the brain. Still, however, the head is hotter than the limbs, especially the hands and feet; and I cannot help thinking that the hair is the only covering which is perfectly safe, either in childhood or age; except in the sunshine or in the storm. There may be--there probably is--some danger in going without hat or bonnet in the hot sun; though I have known many children, and some grown persons, who were constantly exposed in this way, and yet appeared not to suffer from it. But this may be the proper place to state that we are ever in great danger of deceiving ourselves on this subject. If the individuals who follow practices usually regarded as pernicious, while their habits in other respects are just like those of other persons around them who have similar strength, &c. of constitution,--if these individuals, I say, were wholly to escape disease, through life, or if they were to be so much more free from it, and live to an age so much greater than others as to constitute a striking and obvious difference in their favor, we might then safely argue that the practices which they follow are at least without dangers, if not of obvious advantage. But when we see them beset with ills, like other people, it is not safe to pronounce their habits favorable to health, since it is impossible to know whether some of the ills which they suffer are not produced by them. These remarks are applicable to the disuse of any covering for the head in the sun and in the rain. For you will find those who adopt this practice from early infancy,[Footnote: I say, from early infancy; because we may adopt the best habits in mature years, after our constitutions have been broken up by error and vice, without effecting anything more than to keep us from actually sinking at once. Indeed, in most cases we ought not to expect more.] subject to as many diseases as those around them with similar constitutions, but with habits somewhat different; and as our diseases are generally the consequences of our errors in one way or another, it is impossible to say with certainty that some of them might not have arisen from exposure of the head. I should not hesitate, therefore, to advise all mothers to put a light hat or bonnet on the heads of their children, whenever they are to be exposed to the direct rays of the summer sun, or to the rain. And as we cannot always foresee when and where these exposures will arise, and as it is believed that these coverings, if light, will never be productive of much injury while we are abroad in the open air, it will follow that it is better to wear than to omit them.