They consist simply in the following measures:--The careful protection of the child from cold or damp weather, particularly the north-east winds of spring following heavy rains. Croup is most prevalent in those seasons which are cold and moist, or when the alternations of temperature are sudden and remarkable. If the residence of the child is favourable to the production of croup, (for instance, near a large body of water, or in low damp spots,) he should, if possible, be removed to a healthier situation. Sponging or the shower-bath, with cold water and bay-salt, with considerable friction in drying the body, should be commenced in summer, and employed every morning upon the child's rising from bed. The clothing should be warm in the winter and spring, the neck always covered, and flannel worn next the skin throughout the year; but hot rooms, and much clothing when in bed, must be avoided. The diet must be light and nourishing; no beer or stimulant given; and the state of the bowels must be carefully watched. The above precautions are of course particularly necessary to enforce immediately after a recovery from an attack, for there is a great tendency to relapse. If the attack takes place during the winter or spring months, the invalid must be kept, until milder weather, in the house, and in a room of an equable and moderately warm temperature. If in the summer, change of air, as soon as it can be safely effected, will be found very useful. Sect. X.--WATER IN THE HEAD. Water in the head is a formidable disease, and not unfrequent in its occurrence. It is often destructive to life, and the instances are numerous in which it has appeared again and again in the same family, carrying off one child after another, as they have successively arrived at the same age. But notwithstanding its frequency and fearful character, a mother may do much to overcome a constitutional predisposition to this disease, and thus prevent its appearance; as also she may assist greatly in promoting its cure, when it does occur. Hence it is most important that a mother should be acquainted with the measures of prevention; and also, when it does manifest itself, that clear and accurate information should be possessed, upon what may be said to constitute the maternal management of the disorder. ITS PREVENTION.--Whenever there is found to exist in a family a predisposition to this malady, one or more children having suffered from it, a mother must make up her mind, and in the strictest sense of the word, to be the guardian of the health of any child she may subsequently give birth to. And not only during the period of infancy, but during that of childhood also, must she continue the same careful and vigilant superintendence.