104 CONTEMPORARY SCIENCE 



ness. The latter effect especially is one which was the 

 subject of careful study by an expedition of which I was 

 a member, and which during the summer of 1911 spent 

 five weeks at the summit of Pike's Peak, Colorado, alti- 

 tude, 14,100 feet, Bar. 450 mm. We were there enabled 

 to make observations upon hundreds of tourists who as- 

 cended the Peak, and who were acclimatized at most to 

 the altitude of Colorado Springs or Manitou at the foot 

 of the mountain. We saw a number of cases of collapse 

 fainting from oxygen deficiency as shown by the 

 striking cyanosis. 



In the majority of cases, however, tourists who spent 

 no more than the regulation half hour at the summit of 

 the Peak, and then descended, experienced no acute ill 

 effects. Headache and some degree of nausea were com- 

 mon even among these persons, however often develop- 

 ing slowly for some hours after their descent. On the 

 other hand, among persons who remained over night, 

 and were thus exposed for several hours to deficiency of 

 oxygen, the classic symptoms of mountain sickness oc- 

 curred ; and few escaped. Their second day at the summit 

 was marked usually by extreme discomfort headache, 

 nausea, vomiting, dizziness and extraordinary instability 

 of temper symptoms which were strikingly exacerbated 

 by even the smallest use of alcohol. 



Our immediate party passed through these conditions 

 and after two or three days, or in one case nearly a week, 

 re-attained practically normal health. A definite func- 

 tional readjustment had occurred. To illustrate and em- 

 phasize the nature of this readjustment I will quote a 

 recent experiment * of my friend the leader of the Pike's 

 Peak expedition, Dr. J. S. Haldrane. 



He has equipped his laboratory at Oxford with a small 

 lead-lined chamber in which a man can be hermetically 

 closed. The carbonic acid which he exhales is continually 

 absorbed by alkali, so that no accumulation occurs, while 



4 Personal communication. 



