It is impossible to make a definite statement as to the number of times the urine is voided by a healthy infant in each twenty-four hours. In any given case the frequency will differ very much from day to day, depending upon the temperature of the surrounding air and the amount of moisture that it contains. Sometimes it will be necessary to change the napkin every hour during the day and three or four times at night. Again, it may remain dry for six, eight, or even ten hours. Neither condition indicates disease. If, however, the urine is not passed for twelve hours, a careful examination should be made.

Between these two extremes there is a wide range of variation.

As the child grows older the frequency diminishes, and at the age of three years the number of voidings will be reduced to six or eight during the waking hours, and perhaps one at night. When the desire does arise during sleep, the child, if in a normal state, wakes up and demands the chamber, and never passes urine unconsciously. Wetting the bed, therefore, or the involuntary passage of the urine during sleep, is indicative of an abnormal condition and requires investigation. The quantity of urine voided at different ages may be stated as follows, the figures being approximate only:

From birth to 2d year........

From 2d to 5th year..........

From 5th to 10th year........

From 10th to 15th year.......

8-12 fluid ounces. 15-25 fluid ounces. 25-35 fluid ounces. 35-40 fluid ounces.

From a few observations, I am led to believe that the quantity of urine voided by healthy children from the fourth to the seventh years is often not as large as supposed, eighteen to twenty ounces being the average in several cases in which I have made measurements.

The urine of an infant, while it wets, should not stain the napkin.

Examples of Variations in Disease. - In certain cases of bad digestion the urine becomes very concentrated and high-colored, and gives a light yellow tinge to the napkin. When the stain is decidedly yellow, jaundice is indicated, and other symptoms of this condition should be looked for.

In older children a high-colored urine, and one which deposits a whitish or pinkish sediment on standing, is symptomatic of acute digestive disorder, either catarrhal in its nature, or secondary to some acute febrile affection. A smoky, blackish hue, looking as if there had been an admixture of soot, is characteristic of the acute kidney disease that often follows in the wake of scarlet fever. In this state, too, there is a great diminution in the amount passed. The deposition of a "brick-dust" sediment in the napkin, or upon the bottom of the chamber after the urine has been standing for a time, indicates an excessive formation of uric acid.

Painful urination points to inflammation of the bladder or urethra, a narrow orifice, a highly acid condition of the excretion, or stone in the bladder.