Contribution to the Pliysiology of Respiration under tlie Arctic Climate. 149 



apparent contradiction in the results of the two expeditions men- 

 tioned will be explained. 



When we very suddenly ascend into the strong light, the respi- 

 ration-frequency will decrease, in the beginning a great deal, later 

 more slowly, and this effect is in the great majority of cases much 

 stronger than the effect of the decreasing air-pressure; this is seen, 

 for example, in the majority of the Germans, as also in the two 

 Italians from Turin. In the case of the Italians who had been some 

 time among the mountains before the ascent of Monte Rosa, the 

 respiration-frequency is already reduced to a minimum; as a result 

 the decreasing air-pressure could show its influence during the last, 

 considerable ascent, and the frequency rises. 



There are exceptions from the rule; but the view put forth 

 here, which so far as the effect of light is concerned has the advan- 

 tage of being in agreement with the experimental results, gives at 

 any rate a more satisfactory explanation of the observations than 

 that which considers each change in the respiration in the moun- 

 tains as a result of the rarification of the air at high altitudes. And 

 this last explanation is quite useless, when we consider the respira- 

 tion-frequency in my experiments. 



February 09 850 i 0072, fx = ОЗ? 



April 07 (group II) 1007 + 015, ix = 061 



June 07 7-32 + 0067, (i = ОЗб 



August 07 7-09 4: 0066, ц = 031 



November 07 8-38 ± Oil, (x = 050 



January 08 1065 i 022, fi = 111 



For the reasons already mentioned, it will perhaps be best to 

 exclude the experiments 78 and 79 from the November series and 

 experiment 102 from the January one; we then have: 



November 07 8- 14 ± 0044, ц = 018 

 January 08 1036 4= 012, // = 059 



We see again here the same annual periodicity as for the alveo- 

 lar carbonic acid tension and the total volume of air respired; the 

 turning-points of the curve lie in late-summer (minimum) and at 

 the end of winter (maximum). And we see likewise, that the varia- 

 tion in the respiration-frequency from winter to summer is the same 

 as occurs on passing from low to high levels, and that it is just 

 this change we should expect, if the light is the cause of the 

 variations. 



As my experiments, unlike those made among the mountains. 



