1867.] 



Dr. Parkes on the Elimination of Nitrogen. 



45 



Articles. 



Amount, in 

 ounces av. 



Total nitrogen in 

 each article, in 

 grains*. 



Bread 



16 



60-99 





9 (15 raw) 



213 





12 



12 





3 



•I 



Milk 



6 



i6-5 





3 





Butter 



I 



J 



Salt 



•25 







20 



? 





20 



? 



Water 



3 to 9 









302-59 

 or I9'6i grammes. 



The bread was made always in the same way ; the meat (steak) was 

 of an uniform quality, and was carefully selected every day. The whole 

 quantity of food was regularly eaten and at the same time. The only 

 variation was that the potatoes weighed sometimes 12 or 12|-, and some- 

 times 13 ounces (which, however, made very little change in the nitro- 

 gen), and tbat the amount of water drunk, usually 5 ounces at dinner 

 and 2 at supper (on eleven days), was on five days taken in less quan- 

 tity. No alcoholic liquid was taken, and there was no smoking. 



This quantity of food was just sufficient to preserve the body at almost 

 precisely the same weight ; the men were in perfect health. 



During the sixteen days 313'76 grammes (viz. 19 61 x 16) of nitrogen 

 were known to be taken by each man in the food. The following 

 amounts were recovered from the urine in the same time. 



S 303*660 grammes, or 18*97 grammes daily. 



B 307*257 grammes, or 19 '2 grammes daily. 



The nitrogen in the stools (as presently noted) quite made up the 

 difference (10 and 6 grammes) between these numbers and the amount 

 of nitrogen passing in, indeed it rather exceeded it if the average of 

 three days can be applied to sixteen. S. passed regularly rather more 

 nitrogen by the bowels than B., and rather less by the urine. 



The weight of the body at the beginning and end was nearly the same, 

 and it is therefore certain that during the sixteen days no nitrogen 

 escaped by the skin or lungs, but that all passed by the kidneys and 

 bowels. 



The urine was collected from 8 a.m. to 8 a.m., except on the second 

 days of rest and exercise, when it was collected from 8 a.m. to 8 p.m., 

 and from 8 p.m. to 8 a.m. The nitrogen was determined by soda-lime, 



* The nitrogen in the crust and crumb of bread and in the meat was determined 

 once ; the other amounts were calculated. 



