272 DR. ROBERTS ON THE DIURNAL 
falling off again until after the next meal. The determi- 
nations in Table III. are especially worthy of attention in 
reference to this point. This table gives the mean num- 
bers for seven successive days, on which the utmost endea- 
your was made to avoid irregularity or inaccuracy; and 
the densities were all taken by the specific gravity bottle. 
If we now place, side by side, the numbers indicating the 
hourly discharge of acid and the numbers indicating the 
per-centage of acid in the solid urine, from the hour of 
seven p.m., when the alkaline tide subsided, to eight 
o’clock next morning, just before breakfast, the two series 
of numbers will be seen to be entirely different. In the 
former there is a rise and then a fall; in the latter there is 
a continued rise. For comparison, the acidity per 1000 
grains of the liquid urine is also added. 
TABLE XIX. shows the varying results obtained by computing 
the acidity of the urine in three different ways, namely, 
per 1000 grains of the liquid urine; per hour; and per 
100 grains of the solid urine. (The two first columns 
copied from Table L111.) Dinner at Two p.m. 
Per 1000 grains 
Per 100 grains 
Time of day | of liquid urine Renee of solid urine 
7-9 pm. | 0°55 0:48 1:02 
9-11 ,, 0-93 0°77 2°02 
tia 1-07 0°62 ee 
1-7 am. 1:30 0:38 2°37 
3 YS See 0°45 2°50 
From the third column, with which the first also is in 
agreement, we may conclude that when the alkalescence 
of the blood regains its level, after the influence of a meal 
has passed off, it continues nearly at that level until the 
next meal; or, rather, there appears a tendency to a 
gradual diminution in the alkalescence of the blood as 
fasting is prolonged; but I scarcely dare to rely with cer- 
tainty on the calculation for the determination of so nice 
a point. The other tables of means, Nos. I., XI. and 
