3. For reasons which may be seen by the last rule, there should be regular seasons for nursing, and these should be adhered to, especially by night. When very young, once in three hours may not be too frequent; I believe that it is seldom proper to nurse a child more frequently than this. But whenever three hours becomes a suitable period by day, once in four hours will be often enough by night. I will not undertake to say at what precise age children should be nursed at intervals of three and four hours each; because some children are older, _constitutionally_, at three months, than others are at four. There is one grand mistake, however, against which I must caution young mothers; which is, not to indulge the vain expectation that feeble infants will become robust, in proportion to their indulgence. On the contrary, it is the more necessary to be strict with feeble children, _because_ they are feeble. To keep them hanging at the breast to invigorate them, is the very way to counteract our own intentions, and defeat our own purpose. Seasons of entire rest are even more important to their stomachs than to those of other persons. 4. But in order to secure intervals of rest, both to the strong and the feeble, we must avoid the pernicious habit of giving infants pap, and other delicacies, "between meals." Many a child's health is ruined by this practice. Nothing should be put into their stomachs for many months--if they are in health--but the mother's milk. "This," says Dr. Dunglison, "is the sole food of the infant, and is consequently sufficiently nutrient to maintain life, and to minister to the growth, during the earliest periods of existence." [Footnote: Elements of Hygiene, page 271.] In another place, he says, "Milk is an appropriate nourishment at all ages, and is more so the nearer to birth." SEC. 4. _Quantity of Food._ "We all know," says Dr. Dewees, "how easily the stomach may be made to demand more food than is absolutely required; first, by the repetition of aliment, and secondly, by its variety;--therefore both of these causes must be avoided. The stomach, like every other part, can, and unfortunately does, acquire habits highly injurious to itself; and that of demanding an unnecessary quantity of aliment is not one of the least. It should, therefore, be constantly borne in mind, that it is not the quantity of food taken into the stomach, that is available to the proper purposes of the system; but the quantity which can be digested, and converted into nourishment fit to be applied to such purposes." There is a great deal of truth in these remarks; and especially in the closing one, that not all which is taken into the stomach is digested. It is highly probable, that the least quantity which is usually given to an infant is more than sufficient for the purposes of digestion; and that nearly every child in the arms of its mother, is over-fed.