The consequences of measles are not so serious usually, and a more common after effect is trouble with the lungs or bronchial tubes. Pneumonia, croup, and bronchitis very often follow measles, due, as already indicated, to exposure before the body has regained its normal condition. In both scarlet fever and measles the eyes are apt to be affected, and it is very important in both diseases to keep the patient in a darkened room and to forbid use of the eyes in reading or other close work. On account of the complications following scarlet fever and measles, as well as for their greater death-rate, these diseases are more serious than the other two included in this discussion,--whooping cough and chicken pox. _Preliminary symptoms._ The beginning of each of these four diseases is much the same, and the symptoms are likely to be mistaken for those of an ordinary cold. In all of them, the first indication of illness is redness and itching on the inside of the nose and throat with snuffling and discharging from both eyes and nose. Sometimes the throat is affected, and the patient complains of sore throat. Then the cheeks become flushed, headache may follow, and fever begins, so that the patient is in a sort of stupor, unwilling to do anything and glad to lie in bed. In severe cases vomiting may accompany or precede the outbreak of fever. At the outset, the probable reason for the similarity of these four diseases as well as their likeness to a common cold is that the germs responsible for all of them enter the body through the nose and throat and begin their attack upon the membranes there. The action of the germ is followed by the formation of poisons or toxins which are distributed by the blood through the body, causing the fever and what are known as "general symptoms." At the beginning it is not possible to determine to which particular germ the distress of the patient is due, and probably the continued prevalence of these diseases is chiefly owing to the fact that in the early stages and in mild cases throughout, the sufferer is allowed to be at large with every opportunity for spreading the disease. _Contagiousness._ If, whenever a child has a cold accompanied by a fever, the mother would promptly put him in bed in a room by himself, keeping the other children of the family away from the sick room and the invalid under restraint until all possibility of transmitting the disease is over, the number of cases would be greatly diminished. Unfortunately, there seems to be a general impression that such precautions are useless, and that sooner or later every child must have these children's diseases. This is a mistaken notion, and the table already referred to is sufficient evidence to prove the error of this way of thinking.