had severe falls of body temperature whereas the cold adapted ones maintained a 

 steady body temperature. After removal all the controls developed frostbite, but 

 there was none in the treated animals. 



Much work has been done in recent years to investigate the possible develop- 

 ment of acclimatization in man, but the positive findings are few. There have been 

 a number of studies on the Eskimos, who are the best example of people adapted to 

 life in severe cold. 



The most comprehensive enquiry has been that of the Queen's University, King- 

 ston Ontario, under the direction of Dr Malcolm Brown. A group of workers have 

 spent several summers in Southampton Island, which is north of Hudson's Bay, lati- 

 tude 65°N, investigating physiological, nutritional, medical and social aspects, and 

 the work is still in progress. 



The basal metabolic rate of the Eskimo is raised, averaging 30% above normal 

 values for the temperate zone (Hatcher, 1950). Similar raised B.M.R.'s in the Eskimo 

 had been recorded earlier by several workers, but the figures have not always been 

 accepted, as the conditions of measurement were subject to criticism. The work at 

 Southampton Island appears to be free of criticism as a number of repeat determina- 

 tions were made over a period of several weeks and the measurements were made in 

 the Eskimos' huts or tents after a period of at least 8 hours asleep and before arising 

 from bed. So it appears probable that there is a true increase in the B.M.R. in the 

 Eskimo. 



There is no evidence as yet that other people who live in the north develop an 

 increased B.M.R. but not many comparable studies have been carried out. Such work 

 has been attempted on Antarctic expeditions, without any clear results indicating a 

 rise, but this may have been due to the difficulties of measurement. On the present 

 British North Greenland Expedition a physiologist will be carrying out regular deter- 

 minations, and as the members of the expedition will remain in arctic regions for at 

 least a year, it is possible that satisfactory evidence for or against an increased 

 metabolic rate in the cold will be obtained. 



Peripheral blood flows were measured in the forearm at various temperatures in 

 the Southampton Island Eskimo and the values were closely similar to those obtained 

 in similar experiments in this country. There were, however, two possible exceptions 

 Water temperatures ranging from 10°C to 45°C were used in this country, 45*^ being 

 the highest temperature which can be tolerated for periods of two hours. The Eskimos 

 were unable to keep their arms in water at 45°C as blisters developed on their fin- 

 gers. 



At the other end of the temperature scale, it appeared that average blood flow 

 in the Eskimo, when the arm was immersed in water at 10°C, was significantly higher 

 than in similar experiments in this country. Although these results are very sugges- 

 tive, it is clear that further experiments are needed. 



There are many references in the literature on the Eskimo which indicate an im- 

 proved tolerance to cold especially in the hands, such as ability to handle cold 



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