The metabolism of the blood itself 



131 



The change in the blood volume is much less considerable, it is 

 also less constant in different individuals ; for instance, in the first 

 week Douglas' blood volume went down, Haldane's remained practi- 

 cally constant, those of Henderson and Schneider rose a trifle. The 

 factor which perhaps underwent the most constant change was the 

 percentage of haemoglobin in the blood. Cutting out the daily 



DOUGLAS 



OXFORD 



130 

 120 



oo: 



-10. 



o<o 

 o 



SUMMIT OF PIKES PEAK 



II 



o ct 

 ^ a- 



hAutPj 



OXK3RD 



110 

 JOO 



90 



HALDANE 



7 II 



JULY 



15 19 23 27 31 4 8 12 16 20 24 28 I J 9 13 17 21 

 AUGUST SEPTEMBER 



SCHNEIDER 



FIG. 12. 



Abscissae and ordinates on the same scale in each case. 



Ordinates represent percentages of the average values obtained before ascending the Peak 

 (Oxford and Colorado springs) on the particular subject. 

 -= percentage of haemoglobin. 

 = blood volume. 

 = total oxygen capacity or total amount of haemoglobin. 



variations, which were considerable, this reached a maximal value of 

 about 120, in each case taking its original value as 100, but here again 

 it must be observed that the rise was but a gradual one. 



A very complete series of results on the oxygen capacity of the 

 blood have been performed by Mr J. Richards (11) , the manager of a 



92 



