92 SCIENCE PROGRESS. 



be in no difficulty regarding the nature of mountain sick- 

 ness. It is asphyxia. The important feature in the 

 asphyxia of mountain sickness is the reduction in the 

 amount of oxygen supplied to the tissues, but the same 

 effect is produced if, with a limited supply of oxygen to the 

 system, there be from any cause an increased demand for 

 it by the tissues. Muscular exertion is the most familiar 

 example of this, and the greatly increased distress which 

 results from attempts at active movement, is one of the 

 features of mountain sickness. There is another cause of 

 increased demand for oxygen by the tissues which is of 

 importance in connection with mountain sickness, viz., 

 fever. This is well illustrated by Whymper's experiences 

 on Chimborazo {loc. cit.), where at a height of 16,664 feet 

 he and two others of his party had an alarmingly acute 

 attack of what they considered mountain sickness. This 

 came on suddenly after a meal, one of the four members of 

 the party being unaffected. Those affected felt feverish, 

 thirsty, and had intense headache with extreme dyspnoea. 

 These symptoms lessened a good deal next day, and two of 

 the party were able to climb on the third day. No such 

 intense distress was experienced by any of them on climbing 

 more than 3000 feet higher. Whymper recognises that 

 this attack must have had a temporary cause, but he appears 

 to have overlooked the fact that fever is not present in true 

 mountain sickness, and that in all probability it was a case 

 of poisoning with putrid food. Whymper mentions that 

 some of his tinned meat had gone wrong, and it is curious 

 that he should have overlooked the possible connection of 

 this with the attack from which he and the Carrels suffered 

 on Chimborazo. The serious symptoms of asphyxia are only 

 what would naturally be expected to accompany any rise of 

 temperature of the body at high altitudes. 



I now come to the real gist of the matter, the question 

 which Professor Clifford Allbutt hoped would be decided 

 by Conway's observations with the sphygmograph, namely, 

 whether heart-failure is an essential element, indeed the 

 essential element, in mountain sickness ? Asphyxia, from 

 whatever cause, can produce cardiac weakness and dilata- 



