Much practice is necessary before the pulse rate can be counted with any degree of accuracy, and wide experience with both normal and abnormal pulses is required in order to judge its strength, rhythm, or other characteristics. The pulse may be felt most conveniently on the thumb side of the front of the wrist. The pulse should be counted while the patient is lying down, and the watch used must have a second hand. To count the pulse, one should place two or three fingers (not the thumb) on the patient's wrist, and after the pulse has been felt distinctly for a few beats, the exact time by the second hand of the watch should be noticed and the counting begun immediately. It is generally best to count for half a minute, multiply the result by two to get the rate for a whole minute, and then to repeat for another half minute. The two results should agree within two beats, if the patient is quiet. A greater variation than two beats may mean that the pulse rate is varying, but when it is counted by inexperienced persons the apparent difference is generally the result of inaccurate counting, and it may be necessary to count two or three times more. The force of the pulse varies also in different individuals; it is, however, important to notice when it grows stronger or weaker in the same person. Normally the pulse-beat is regular like the ticking of a clock; it is called irregular if a few rapid or slow beats are followed by others of a different rate. During sickness the pulse should be counted whenever the temperature is taken, or oftener; and the result should be written down at once. The pulse of a sick person often shows changes both in rate and character; these changes are generally important and should be noticed. RESPIRATION.--Variations in the rate and character of respiration or breathing should be noticed. The normal rate of respiration for an adult at rest is 16 to 20 each minute, but it may be much faster, especially during muscular exercise. In babies the rate is about 30 to 35 a minute, and 20 to 25 in little children. The respirations, especially of babies, can best be counted during sleep by placing the hand lightly on the chest or abdomen. Since the respiration rate is partly under a person's control, it is almost sure to alter if the patient knows it is being counted; hence when the patient is awake it is better to keep one's fingers on his wrist, to place his hand upon his chest, and then to count the rise and fall of the chest while apparently counting the pulse. Sometimes it is possible to count the respirations merely by watching the rise and fall of the nightgown or bed clothes. The respiration is usually counted for a full minute. A watch with a second hand must be used, and the result should be recorded immediately.