354 Dr. Parkes on the Elimination of Nitrogen. [Jan. 31, 



compared with the first period, there is no evidence in either case of any- 

 increased excretion ; on the third day, indeed, the nitrogen was below that 

 of the first period in each case. 



The balance of ingesta and egesta was as follows on the third day of 

 this period : — 





S. 



T. 



Weight of body at commencement. . . 



67-1 



50-07 





67-08 



50-08 





-20 



+10 



2891-7 



2877-5 





1808-7 



1922-5 





134-9 



71 





968-1 



894 



These numbers are fairly accordant with those of the first period, 

 except that the intestinal excretion in T. was slightly less, and the urinary 

 rather more. 



The conclusions which can be drawn from the above experiments are 

 not altogether accordant with those of Professors Pick and Wislicenus. 



The decrease in the urea during the first thirty-six hours of the exer- 

 cise-period, as compared with the rest-period, on a diet without nitrogen, 

 which occurred in these two men, is, I think, conformable with the results 

 obtained by the two experimenters mentioned ; but this is not the case with 

 the increase in the urea which I found in the last twelve hours. Yet that 

 this increase is real is shown, I believe, by the accordant results in the 

 two men, and by the increase of the total nitrogen of the exercise-period 

 as determined by soda-lime. 



The relative greater increase in my experiments of the nou-ureal nitro- 

 gen (which makes me believe that an excess of nitrogenous compound 

 other than urea, and possibly creatinine especially, was produced by 

 the exercise) is not perceptible in their experiments, yet I cannot but be- 

 lieve that the fact was so, as it comes out with great clearness in the two 

 men. The following Table shows this. 



Relation of ureal to non-ureal nitrogen, the former being taken as unity. 



S. T. 



Before rest-period 1 to 1*1 1 to 1*108 



Rest-period 1 to 1-042 1 to l* 13 



After rest-period 1 to 1-009 1 to 1-116 



Work-period 1 to 1-126 1 to 1-178 



After work-period 1 to 1*08 1 to l-06(?) 



(three days). 



The reason which makes me believe the results are real, is the fact that 

 the individual relation of the ureal and non-ureal nitrogen is preserved ; 

 that is to say, in T. the non-ureal nitrogen is, under normal circumstances, 

 a little in excess as compared with S. ; the same relative excess is also 

 found in the work-period. 



