Contribution to the Physiology of Respiration under the Arctic Climate. 165 



Smith's results, which are in decided opposition to mine, are 

 everywhere cited where these questions are discussed and without 

 criticism; they thus seem to have obtained general recognition. It 

 seems to me, however, that various objections can be raised against 

 these experiments. 



In the first place the person investigated on did not keep still. 

 The author mentions at several places, that he was indisposed and 

 uncomfortable, often changing his position; he would partly sit, 

 partly stand during the experiments. He mentions, further, that he 

 held on the respiratory mask with the hands, w hen he had no 

 other use for them. This muscular activity brings an element 

 of uncertainty into the results, which cannot be calculated and 

 which, especially in the case of quite few experiments in one month, 

 may have an influence out of proportion to its value. In the second 

 place it is not known, whether Smith lived on the same kind of 

 food the whole year round; but it is most probable that he did not 

 do so. He himself mentions, that higher "carbonic acid values" 

 were obtained as a rule on the Monday, as one does less and eats 

 better on the Sunday. And in his curve for the amount of carbonic 

 acid given off, there is a very marked rise from the ^'^'/l2 to the ^" i, 

 which makes one think in this connection of the intervening Christ- 

 mas festivities. To this must be added that the bodily weight is 

 not given; the production of carbonic acid is given in absolute 

 values, not per kilo, of body weight. 



Lastly, it is not quite clear to me, where Smith has obtained 

 the above-mentioned values for the annual period. In his main 

 work we find the series given below, which if we except the fre- 

 quency is far from giving the results quoted above. The value 

 agrees in the case of the frequency, if we calculate the percentage 

 from the lowest value, which is not quite correct in this case. In 

 the short summary from which the numbers cited are taken, no 

 experiments are given. 



It appears from the summary below, that the months of April 

 and May take up a special position; considering the last column, the 

 frequency, it strikes one at once, that there is quite a remarkable 

 jump from March to April. From this series we might just as well 

 conclude, that the frequency falls throughout the year and then 

 suddenly rises from March to April. To judge from the numbers 

 the respiration in April and May has undoubtedly been forced. 

 And the reason for this forced respiration is not far to seek; it lies 

 in the imperfect training of the individual experimented on, who is 

 not quite accustomed to his apparatus and does not feel comfortable 

 during the experiments. Whilst the CO g- curve, excluding the rise 



