The first point to ascertain is the presence or absence of fever; that is to say, whether, and how much, the temperature of the body is higher than natural. If the temperature is not higher than natural, it may be taken as almost certain that the child neither has any inflammatory affection of the chest, nor is about to suffer from any of the eruptive fevers. The temperature, however, cannot be judged of merely by the sensation conveyed to the hand, but must be ascertained by means of the thermometer.[4] In the case of the grown person the thermometer is placed either under the tongue, the lips being closed over it, or in the armpit, and is kept there five or six minutes. In young children, however, neither of these is practicable, and I prefer to place the instrument in the groin, and crossing one leg over the other, to maintain the thermometer there for the requisite five minutes. The temperature of the body in health is about 98.5 deg. Fahr. in the grown person, and very slightly higher in childhood; but any heat above 99.5 deg. may be regarded as evidence that something is wrong, and the persistence for more than twenty-four hours of a temperature of 101 deg. and upwards, may be taken as almost conclusive proof of the existence of some serious inflammation, or of the onset of one of the eruptive fevers. At the same time it is well to bear in mind that temporary causes, such as especially the disorders produced by over-fatigue, or by an over-hearty or indigestible meal, may suddenly raise the temperature as high as 102 deg., or higher, but the needed repose or the action of a purgative may be followed in a few hours by an almost equally sudden decline of the heat to the natural standard. It is well to learn to count the pulse and the frequency of the breathing; but to do the former accurately, requires practice such as is hardly gained except by hospital training; and indeed, with few exceptions, the value of the information furnished by the pulse is less in the child than in the adult. The reasons for this are obvious, since the rapidity of the circulation varies under the slightest causes, and the very constraint of holding the sick child's hand makes it struggle, and its efforts raise the frequency of the heart-beats by ten or twenty in the minute. The place at which to seek the beat of the pulse is at the wrist, just inside and below the protuberance of the wrist-bone; but if the child is very fat it is often difficult to detect it. When detected it is not easy to count it in early infancy, for during the first year of life the heart beats between 120 and 130 in the minute, diminishing between that age and five years to 100, and gradually sinking to 90 at twelve years old. In proportion, moreover, to the tender age of the child, is the rapidity of its circulation apt to vary under the influence of slight causes, while both its frequency and that of the breathing are about a third less during sleep than in the waking state.