4 August Krogh and Marie Krogh. 



In the spring of 1907, however, Dr. Benedict of the Carnegie 

 Nutrition Laboratory visited Copenhagen. One of us had a consulta- 

 tion with him on the plans which we entertained. He was very in- 

 terested in the plan and offered to have all the samples which could 

 be preserved analysed for us in his large laboratory. 



In 1906 a Danish Arctic Station for biological research had been 

 erected near Godhavn on the island Disco (lat. 69°15' N. long. 53°W.) 

 in West-Greenland. Here was a laboratory which, though not equipped 

 for physiological work, could render assistance on a large number 

 of points. It was managed by our friend, the botanist M. P. Porsild 

 and we were most kindly invited to live and work at the Station. 



The whole expedition and investigation was finally made pos- 

 sible by a grant of kr. 4500 from the Danish Carlsberg Fund. 



We wish to express our sincerest thanks to the Carlsberg Fund 

 for its liberal grant of money, to Dr. Benedict, Director of the Nutri- 

 tion Laboratory of Boston for the great aid given us with regard to 

 the analysis of our samples and for valuable advice on a number of 

 points, to Mr. M. P. Porsild, Director of the Danish Arctic Station 

 for his great hospitality and his help in dealing with the natives, to 

 Mr. Nygaard Assistant of the Arctic Station, whose ingenuity and 

 technical skill helped us to overcome several serious difficulties en- 

 countered during the erection of our apparatus, and finally to the 

 Administration of the Colonies in Greenland who did all in their power 

 to further our work. 



Our final plans were as follows: We would go up to the Arctic 

 Station in the spring and there erect in the open a respiration ap- 

 paratus constructed beforehand and capable of accomodating two 

 subjects. By means of this chamber we would make experiments 

 of 4 — 5 days duration with determinations in two to three-hour periods 

 of oxygen intake and CO^ output. The urine should be collected in 

 similar intervals, measured and samples preserved. The subjects 

 should be fed chiefly on sealmeat, their favourite food, and samples 

 both of the food and the feces collected for subsequent analyses. 



These plans were carried through, practically completely, and 

 though we failed to obtain clear and conclusive evidence on the point 

 which we had specially set out to study, the data collected may ne- 

 vertheless be of some value. They represent the one extremity of 

 that range of dietaries on which man can live and work, namely a 

 diet which is practically exclusively of animal origin and contains 

 an enormous amount of N and a minimum only of carbohydrates, 

 and our observations go to show how little the diet matters after all. 



We may perhaps be justified in giving a brief general narrative 

 of the expedition which will show some of the difficulties with which 

 one has to contend in experiments of this kind and explain to some 

 extent why we were unable to accomplish more than we did. 



