1867.] Dr. Parkes on the Elimination of Nitrogen, 51 





s. 



B. 



x\j\ja.L iiltlU^Cll 111 Uxlllc 111 tWU tldyo iCou ••• 



grammes. 

 38*274 

 39-292 



grammes. 



38'943 

 39-918 



i-oi8 



o'975 



The first day following the exercise was a day of almost complete rest ; 

 the nitrogen in both men was increased considerably over the average 

 of the first and third periods, and very greatly indeed over the amount 

 of the first day of the third period, the excess being 5-33 and 3 -568 

 grammes over that day. This was the most considerable variation in 

 the period of experiment. The nitrogen continued high all through this 

 period, the result being that in the four days S. excreted 84-216 and B. 

 80*368 grammes, or 13 and 6 grammes respectively in excess over the 

 first period of four days. It is clear indeed that during this period, the 

 excretion of nitrogen must have been greater than the ingress. 



I will not trace the changes in the urea in such detail. They were 

 almost identical wdth those in the total nitrogen. 



In the first period the amount of urea was almost precisely the same 

 in the two men. In the rest-period it increased nearly 2 grammes daily 

 in each man, fell during the third period to the former average, decreased 

 greatly during the first thirty-six hours of the exercise-period as com- 

 pared with the rest-period, and increased in the last twelve hours ; in 

 the last or after-work period it also increased, though in a less propor- 

 tion than the toteJ nitrogen. 



The changes in the non-ureal nitrogen were also very similar in the 

 two men, but will be best followed in the case of B., in whom the 

 excretion of non-ureal nitrogen was more steady from day to day than 

 in S. It was very slightly and immaterially increased in the rest-period, 

 fell as slightly in the after rest-period, remained the same during the 

 exercise-period, and increased to nearly double in the last four days. 

 In S. it increased more in the rest-period and in the exercise-period 

 than in B., and still more in the last four days. This increase in the 

 non-ureal nitrogen after exercise is confirmatory of the results formerly 

 obtained on this point. 



If these results are looked at as a whole, it will be seen that though 

 the changes in the amount of nitrogen were for the most part not great, 

 still they were decided and evident changes, and occurred precisely in 

 the same way in the two men. The coincidence in the changes in the 

 urea and in the total nitrogen (determined by such diff'erent processes) 

 is a strong argument that the results were real. Throughout the whole 

 time the food was precisely the same, and the modifications were there- 

 fore not owing to variation in the ingress of nitrogen. 



There was some variation in the amount of urinary water ; but the 



e2 



