Children of sound health, who are judiciously fed, and have sufficient exercise, very seldom need aperient medicine. Errors in diet, a want of proper attention to the state of the skin, insufficiency of air and exercise, in fine, a neglect of those general principles which have been laid down for the management of health, and upon the observance of which the due and healthy performance of every function of the body depends, are the sources of bowel derangements, and particularly, at this age, of costiveness. I feel assured, however, that some children are more troubled with costiveness than others, from the simple but important circumstance of their not being early taught the habit of relieving the bowels daily, and at a certain hour. There is a natural tendency to this periodical relief of the system, and it exists at the earliest age. And if the mother only cause this habit to be fairly established in infancy, she will do much towards promoting regularity of her child's bowels throughout life. The recollection of this fact, and the mother's acting upon it, is of the greatest importance to the future health and comfort of her children. If the bowels are accidentally confined at this age, castor oil is certainly the best aperient that can be given: it acts mildly but efficiently, clearing out the bowels without irritating them. The dose must be regulated by the age, as also by the effect that aperients generally have upon the individual. Great care must in future be taken to avoid the cause or accidental circumstance which produced the irregularity. When the bowels are habitually costive, much care and judgment is necessary for their relief and future management. Fortunately this condition is very rare in youth. The activity and exposure to the air, usual at this period of life, render purgatives unnecessary, unless, indeed (as just mentioned), some error in diet, or some unusual circumstance, render them accidentally confined. Should, however, the foregoing state exist, medicine alone will avail little; there are certain general measures which must also be acted up to, and most strictly, if the end is to be accomplished. They consist, principally, in an observance of great regularity with respect to the time of taking food, its quality, quantity, and due mastication; regular and sufficient exercise, horse exercise being particularly serviceable; the shower-bath, or daily ablution; early rising (the indulgence in the habit of lying in bed always predisposing to constipation); and, lastly, the patient habituating himself to evacuate the bowels at a certain hour of the day. After breakfast appears to be the time when the bowels are more disposed to act than at any other part of the day; this is the time, then, that should be chosen. All these points must be sedulously observed, and upon the principles laid down in the various chapters upon these subjects, if habitual costiveness is expected to be overcome. SECT. IV.--WORMS.