[ T47 ] 
XXIX. On the Mimination of Urea and Urinary Water ^ in relation to the Period of the 
Pay, Season, Exertion, Food, Prison Piscipline, Weight of Body, and other influences 
acting in the Cycle of the Year. By Edwaed Smith, M.P., LLB., F.B.S., Assistant 
Physician to the Hospital for Consumption and Diseases of the Chest, Brompton, Cor- 
responding Felloio of the Academy of Sciences and Arts of Montpellier, and of the 
Hatural History Society of Montreal, &c. 
Eeceived April 18,^Eead May 30, 1861. 
I PUEPOSE in the following communication to state the results of two series of experi- 
ments in reference to urea and minary water in the healthy human system, with a view 
chiefly to show their relation to exertion, food, nutrition, period of the day, and season 
of the year, and to enable me to contrast these relations with those of carbonic acid, 
which I had the honour to lay before the Koyal Society in 1859, and which have been 
pubhshed in the Philosophical Transactions. 
The first series of inquiries was made upon myself, and was continued from January 
18, 1860, to March 18, 1861, and numbered 1633 observations upon the urinary water, 
and 1073 analyses for urea on 336 days. The observations were fewer in the months of 
September and October than in the other months; but from January to the end of July 
1860, throughout nearly the whole of October, and from the early part of November 
until the end of the inquiry, the observations were not intermitted. 
[The inquhies w'ere continued daily until March 18, 1862 ; so that the whole series 
comprehends a period of two years and two months, with 635 days of actual daily 
observation, and nearly 1400 analyses for urea*.] 
The ordinaiy- food was taken during this period ; and each part of it was weighed and 
recorded, except in some of the summer months. It was of a simple kind, consisting of 
coffee and bacon for breakfast, at about 9 a.m.; one kind of meat, v/ith vegetables and 
pudding, at 2 to 3 p.m.; tea •v\'ith bread and butter at 6 P.M., and coffee with bread and 
butter at 9 or 10 p.m. On Tuesdays and Fridays coffee and bread and butter were 
taken at 1^ p.m., and dinner, with tea, at 5 to 6 p.m. No kind of alcoholic liquor was 
ordinarily taken ; and whenever any unusual kind or quantity of food was eaten, or the 
hour of dining was changed, it was duly recorded. The following is an average example of 
the dietary used daily : — cooked meat, 3 oz. ; cooked bacon, 2 oz. ; butter, 1 oz. ; bread, 
14 oz. ; pudding, 9 oz. ; potatoes, 7 oz. ; sugar, 2 oz. ; milk, 6 oz. ; coffee, 35 oz. ; tea, 
15 oz. ; water, 10 oz. 
The general habits were not interfered with. There was a fair amount of activity, 
both of body and mind, except on Sunday, when the rest was almost perfect. The 
• The portions of the following paper which are enclosed in brackets have been added since the paper was read. 
MDCCCLXr. 5 I 
