Extreme nervousness in childhood carries with it a certain liability towards what is known as "delicacy of constitution." The sensitiveness of the children is so great that they react with striking symptoms to disturbances so trivial that they would hardly incommode the child of more stable nervous constitution. For example, a simple cold in the head, or a sore throat, may cause a convulsion or a condition of nervous irritability which may even arouse the suspicion that meningitis is present. Or, again, a little pharyngeal irritation which would ordinarily be incapable of disturbing sleep may be sufficient to keep the child wide awake all night with persistent and violent coughing. The little irritating papules of nettlerash from which many children suffer are commonly disregarded by busy, happy children during the day, and even at night hardly suffice to cause disturbance. The nervous child, on the other hand, will scratch them again and again till they bleed, tearing at them with his nails, and making deep and painful sores. The temperature is commonly unstable and readily elevated. Moreover, feverishness from whatever cause is often accompanied by an active delirium, which is apt to occasion unnecessary alarm. This symptom of delirium is always a manifestation of an excitable temperament. I remember being called to see a young woman who was thought to be suffering from acute mania. Examination showed that she was suffering from pneumonia in the early stages. It was only later that we discovered that she had always been of an unstable nervous temperament, and had been in an asylum some years before. Those of us who are fortunate in possessing a placid temperament and have developed a high degree of self-control are not likely to show delirium as a prominent symptom should we fall ill with fever; just as we should not struggle and scream too violently when we "come round" from having gas at the dentist's. Looked at from this point of view, it is natural for all children to become delirious readily, and this tendency is peculiarly marked in those who are unduly nervous.