CHAP. XIX. FACTS. 381 



Aeronauts never remain a sufficiently long time at considerable 

 elevations to be able to say whether the acceleration is temporary 

 or permanent. De Saussure and others seem to have been under 

 the impression that it always • accompanies increase in the rate of 

 respiration. In the passage given on p. 380 from Voyages dans les 

 Alpes, he states as a fact that '^^at the same time the respiration is 

 accelerated^^ [under diminution of pressure] ^^the circulation is 

 also quickened '' ; and from the general tenour of the passage it is 

 evident he considered that the joint increase in the rate of the 

 respiration and circulation was continuous, when remaining in a 

 state of rest at great elevations, at one constant pressure. 



This was not our experience amongst the Great Andes of the 

 Equator. At the first, following the general (and probably the 

 invariahle) rule with those who sustain a considerable diminution 

 in pressure in a comparatively short time, there was a large and 

 very unpleasant increase in the rate of my pulse, accompanied by 

 a considerable rise in body temperature ; and (although they would 

 not permit any observations to be made on their persons) I do not 

 doubt that the same occurred with Jean-Antoine and Louis Carrel, 

 as they spoke of str6ng feverishness. But while continuing to live 

 with the barometer standing at 16 '500 inches the pulse slowed 

 down and ultimately fell to its normal rate ; the temperature of 

 the body also fell until it got to its normal degree ; and the 

 subsequent fluctuations which occurred in the rate of the pulse and 

 in the temperature of the body,'' even whilst sustaining further 

 diminution of pressure, were only such as could be assigned to 

 common causes. The righting of our condition occurred in the 

 ordinary course of nature, without having recourse to artificial use 

 of oxygen;* and I ask (1) If the unpleasant effects which were 

 experienced upon Chimborazo [gaspings, feverishness, intense head- 

 ache, and an indescribable feeling of illness pervading almost the 



1 See Appendix F. 



2 During the whole journey I did not, personally, consume so much as an ounce 

 of Chlorate of Potash, 



