OF UEEA AA'D TJEINAKY WATEE. 
775 
at other periods, and to determine the influence of meteorological phenomena over the 
daily production of this excretion. At that period, moreover, the only disturbing cause in 
operation was the slight exertion required whilst dressing. This was called the “ basis 
quantity,” and corresponds to a similar inquiry recorded in my paper on the evolution 
of carbonic acid, published in the Philosophical Transactions, 1859. But beyond these 
three periods of inquiry there was commonly a fourth, viz. that which intervened 
between the emission of the basis quantity and midday ; and further, an analysis of the 
mine was made at frequent inteiTals in the afternoon during the months of January, 
February, and March 1860. 
Another series of inquiries was expressly instituted to determine the hourly emission 
with the utmost exactitude ; and on three days the urine was passed at every hour, and 
on two other days at every quarter of an hour during the day. 
The food was taken at the hours indicated in the earlier part of this paper. I shall 
now proceed to describe the result of the fu-st series of inqumes. 
Belations of Urea. 
Plate XXXIII. exhibits the hourly quantities of urea and urinary water at the four 
periods just mentioned, "viz. the whole day, the night, the basis quantity, and the period 
until midday, on each day of the inquuy throughout the year, and the following Table 
contains the weekly and monthly averages of the daily quantities. 
