14 



Mr. W. North. The Influence of 



[Nov. 15, 



requires, I regulated my diet for some four or five days before begin- 

 ning an experiment, and took rather more exercise than usual in order 

 to get rid of any possible surplus in the body ; in the latest experiments 

 I have adopted the plan of abstaining from food on the first day of an 

 experiment, in order to effect the discharge of this surplus, and I am 

 inclined to regard this as the best method to pursne. 



I then place myself upon a regulated diet of accurately known 

 composition for nine or ten days, and about the middle of the period 

 I perform a certain amount of muscular labour. In all experiments 

 made thus far the labour consisted in walking a known distance, and 

 carrying a load whose weight was accurately determined. By observing 

 the relation of the nitrogenous intake to the output from day to day, 

 I was enabled to determine with very considerable accuracy the effect 

 produced by the labour upon it. In addition to the nitrogen the 

 phosphoric and sulphuric acids were accurately determined in the 

 food and excreta, and so I was able to institute a comparison, and 

 observe the effect of the exercise in modifying the relationship. 



It is impossible in a brief abstract to enter into the immense mass 

 of detail which these experiments involve, bat the following tables 

 will, I think, suffice to exhibit the general nature of the results 

 obtained. 



Experiment I, 1882. 



Nitrogen of urine. 



,, faeces 

 Total excreta 

 Total ingesta 



Difference 



P 2 5 of urine. . . . 

 P £ 5 of faeces.... 

 Total excreta 

 Total ingesta 

 Difference 



Daily. 



Before 

 work. 



After 

 work. 



Difference. 





14-15 



15 -74 



+ 1-59 





2-48 



2-15 



-0-33 





16 '66 



17-89 



+ 1-23 





2 -01 



2-00 



-o-oi 





2-54 



1 -85 



-0-P9 





4 *55 



3-84 



-0-71 





2-76 



3 00 



+ -24 



Wnole 

 experiment. 



Daily. 



135 



•33 



15 



03 



20 



•69 



2 



•29 



156 



•02 



17 



•32 



158 



•78 



17 



64 



2 



•76 







32 



18 



•00 



2 



00 



19 



44 



2 



16 



37 



•44 



4 



16 



34 



•84 



3 



87 



2 



-60 







29 



