Instances of powers of _prolonged nursing_ in mothers are not uncommon. Indeed it is the habit among some nations to suckle children until they are three or four years of age, even though another pregnancy may intervene, so that immediately one child is succeeded at the breast by another. In those who have thus unnaturally excited the mammary glands, an irrepressible flow sometimes continues after the demand for it has ceased. Dr. Green published, some years ago, in the _New York Journal of Medicine and Surgery_, the case of a woman, aged forty-seven, the mother of five children, who had had an abundant supply of milk for _twenty-seven years_ consecutively. A period of exactly four years and a half occurred between each birth, and the children were permitted to take the breast until they were running about at play. At the time when Dr. G. wrote, she had been nine years a widow, and was obliged to have her breasts drawn daily, the secretion of milk being so copious. When, therefore, it is desirable, on account of the feebleness of the child, to protract the period of nursing, a wet-nurse should relieve the mother at the end of twelve or fifteen months. RULES FOR CARE OF HEALTH WHILE NURSING. From what we have previously said of the influence of the nervous system over the quantity and quality of the milk, and the instances we have adduced of the danger to the infant of all violent passions--such as anger, terror, anxiety, and grief--on the part of the mother, it will be apparent that it is of the greatest moment, during the whole course of nursing, to maintain a tranquil state of mind. Pleasing and peaceful emotions favor the normal secretion of milk, and go far towards securing the health of the child. When strongly affected by any powerful feelings, mothers should not give the breast, but should wait until they have calmed down to their usual tenor of temper. A case is related of a woman who was always excited by a highly electrical state of the atmosphere, and particularly during stormy weather. If when thus influenced she nursed her child he was sure to fall into convulsions; while, if she delayed doing so until this nervous excitement had passed, no unpleasant symptoms occurred. But we have already dwelt at length upon this subject in speaking of the influence of the mind of the mother over the child at her breast, and need not therefore recur to it. The _food_ while nursing must be nutritious and varied, though simple and unstimulating; and should consist both of meat and vegetables, soups, fish, flesh, and fowl, either in combination or succession. When the digestion requires stimulation and aid, a glass of mild ale twice a day will be useful. Wines, brandy, and whisky should not be taken without the advice of a physician. Moderate exercise in the open air and regular habits are necessary. A defective or excessive diet, fatigue, loss of rest at night, and irregularities and excesses of all kinds are unfavorable to mother and child.