Contribution to the Physiology of Respiration under the Arctic Climate. 95 



other days, owing most probably to a slight enteritis, which became 

 apparent later in the day. 



It w^as possibly due to the increasing feeling of cold during the 

 experiment, that the frequency of the respirations several times de- 

 creases towards the end of the experiment. This is the case in 

 most of the experiments in the first half of the series, whilst it is 

 not present in the later, when the temperature in the room was 

 higher and the cold less felt after the colder days preceding. 



The total amount of air respired varies but little. The 



average of 12 experiments was 384 4- 2*4, ii = 1246 or 3-25 '^/o of 



the average. Experiment No. 132 gave a large positive deviation, 



experiment No. 128 the lowest; but neither of these deviations seems 



in itself improbable. 



The amount of carbonic acid in the alveolar air is, 



д£ . a J 



as already mentioned, calculated from Bohr's formula X = — т . 



A — a 



A is the volume of an expiration, a of the "dead space"; E and I 

 the percentage of carbonic acid in the expired and inspired air 

 respectively. The average amount of an expiration is given in the 

 table. The "dead space" I have judged to give 300 cc, 150 cc. for 

 the mask, connecting tube and valvular apparatus, and 150 cc. for 

 my own person; the first of these was determined by means of 

 water ^. The calculated amounts for the carbonic acid are given in 

 the table; as the carbonic acid in the inspired air varies very little 

 and has here but little influence on the estimated alveolar air, I 

 have been content with two determinations for it. 



According to Bohr's reasoning, the carbonic acid in the alveolar 

 air is found from the expiration phase. It will be less during in- 

 spiration and the difference will be all the greater, the greater the 

 volume of the single breaths drawn. The accuracy of the deter- 

 mination will depend here, when the average volume is considered, 

 only on the nearness with which we are able to determine the 

 amount of the "dead space". As I have increased this by the whole 

 arrangement of my apparatus, and as the increase can be measured, 

 provided that all the air in the mouth and valvular apparatus takes 

 part in the process, the error introduced in the conclusions will be 

 comparatively small. The amount of the personal "dead space" is 

 variously given; I have taken the average of the values. 



LoEWY^ has endeavoured to determine the "dead space" in 



^ A correction for temperature has not been made, as the error thus introduced 

 is of no importance worth mentioning and because the exact temperature could 

 not be determined. 



- Pflügers Archiv. Bd. 58, 1894, p. 416. 



