_Simple diarrh[oe]a_ usually comes on gradually, and is some days before it grows severe, or passes into the more dangerous dysentery. Simple precautions will often arrest its progress, and, among them, rest in bed is one of the most important. Over and over again I have known a diarrh[oe]a which had continued in spite of all sorts of medicines so long as the child was running about, cease at once when the child was kept for a couple of days in bed. The reason of this is obvious; constant movement of the intestines themselves, which serves so important a part in maintaining due action of the bowels, is increased by the upright position and by movement, and is reduced to a minimum by the horizontal position. A second precaution concerns the diet; solid food and animal broths should for a time be discontinued, and arrowroot, milk and water, and rice substituted for it, for a day or two, with isinglass jelly, and the white decoction of which I have already spoken. It is not always that astringents are suitable at the beginning of an attack, and the sending to the neighbouring chemist for diarrh[oe]a medicine, which often contains an unknown quantity of opium, is always risky, frequently mischievous. In a first attack of diarrh[oe]a, the doctor should always be consulted, for when it is associated with disorder of the liver a mercurial may in the first instance be needed, or possibly very small doses of a saline medicine, such as Epsom salts, with the addition of a few drops of the tincture of rhubarb; or, again, if the diarrh[oe]a sets in with profuse watery discharges, sulphuric acid for the first few hours is often of extreme service. It is at a later time that direct astringents commonly have their use; and the mother, who in her child's first attack of diarrh[oe]a has had the advice of a judicious doctor, will often be helped by him to manage for herself slight returns of the ailment.