Theories and Experiments 231 



the rarity of the air or the supposed influence of snow . . . We can 

 assert that these are the same sensations felt by ordinary travellers 

 when they approach the summit of any mountain whatsoever. 



I beg the reader to refer to the actual words of Barry, which I 

 quoted previously (See page 95) ; he will find, I hope, in them a 

 proof of the necessity of verbatim quotations. 



It is interesting to note that M. Martins, 59 who was later to 

 become so sick on Mont Blanc as if by a kind of punishment for 

 his skepticism, at that time shared these sentiments. Accounts of 

 mountain sickness left him very incredulous: 



As for us (he says), occupied night and day with our observa- 

 tions, we also tried to test our sensations to find out whether this 

 lofty habitation (2680 meters) had any physiological effect upon our 

 organs. But it was in vain . . . Since my sojourn there, I have read 

 again all the accounts of ascents of Mont Blanc, from de Saussure to 

 Mile. d'Angeville, and the sensations felt by these travellers can be 

 explained very easily by fatigue . . . 



Of course the air of the mountains is more rarefied, but it is also 

 more alive . . . The liveliness of the air, added to its rarity, refreshes 

 the traveller and doubles his powers; for the chemical composition is 

 the same. (P. 213.) 



I confess that I am surprised that a man with so clear and so 

 perspicacious a mind could have used such expressions. What do 

 the words "a more alive air" mean.? The Swiss peasants who saw 

 the celebrated professor of Montpellier collecting air in balloons 

 and sending it to Paris, and who thought that he would make some 

 illustrious patient breathe it, shook their heads and said: "Our air 

 will be dead when it gets there." We see that essentially they 

 thought like M. Martins. 



Dr. Rey, G0 whose work is often quoted, and who, without seem- 

 ing ever to have made an ascent, wrote a dogmatic article about 

 mountain sickness, reaches the theoretical explanation after an 

 enumerative description. He sees, and in this he does not have 

 the merit of invention, that rarefied air is the cause of all these 

 symptoms: 



It is neither the fatigue which removes the power of breathing, 

 nor the difficulty of breathing, nor an incomplete respiration which 

 cause the exhaustion, as has sometimes been said; it is the decrease 

 in the density of the air . . . 



These effects are due to the relaxation of the fibre caused by the 

 decrease of the compressing power of -the air, the explanation of 

 which follows. (P. 334.) 



The usual calculation on the difference in the weight sustained 

 by the body at different altitudes follows. At the Saint Bernard 



