CHAP. XVI. A WALK ON THE QUITO ROAD. 299 



had experienced pressures loioer than IG'5 inches (the pressure at 

 the second camp on Chimborazo). It seemed probable that we had 

 ascertained the worst that would happen to us, iwovided luc did not 

 have to sustain still lower pressures. 



This does not, however, at all inform one whether our rate 

 uj^on Illiniza was inferior to that which we should have attained 

 upon the mountain if it had been placed at a lower level (that is 

 to say, if a higher pressure had been experienced whilst ascending.), 

 and on this point there is very little enlightenment to be obtained 

 by comparing the Illiniza rate with the rates of other persons upon 

 equally elevated mountains in different parts of the world ; for 

 the difficulties presented upon mountain ascents vary so much as 

 to make it nearly, or quite impossible to select any two upon 

 which one might expect to attain precisely the same rate. The 

 ascent of the Tetons, for example, cannot be compared with that of 

 Pike's Peak, or the Aiguille du Dru with Altels. The natures of 

 these mountains are dissimilar ; and, in order to arrive at anything 

 like just conclusions concerning the effects of diminished pressure, 

 comparisons must be made between walks of a similar nature, 

 taken under similar conditions. This brings me to what I consider 

 one of the most interesting incidents of the journey, namely, a 

 walk taken on the Quito road, at an elevation of about 10,000 

 feet, for comparison against a similar walk slightly above the 

 sea-level. 



Before starting for the Great Andes of the Equator, I had 

 considered in what manner one might best determine whether 

 diminution in atmospheric pressure weakened the bodily powers ; 

 and no method appeared so practicable as comparison, at different 

 pressures, of the natural and habitual rate of walking. The 

 simplicity of this idea may perhaps excite ridicule amongst those 

 who are not aware of the regularity with which it is possible to 

 walk, and of the precision with which a pedestrian may estimate 

 his rate. Even amongst those who follow pedestrianism profes- 

 sionally, there are probably few who will admit the possibility 



