378 TRAVELS AMONGST THE GREAT ANDES, chap. xrx. 



mentions twenty litres per minute as the least quantity that a 

 party of three persons would require at an elevation approximately 

 corresponding to the upper 5000 feet of Mount Everest. Thus, if 

 a trio should encamp upon Mount Everest at the height of 24,000 

 feet, and pass an entire day in ascending and descending the final 

 5000 feet, and a second night at the camp (say thirty-five hours in 

 all at 24,000 feet or higher), the least quantity that would be re- 

 quired (according to Prof. Paul Bert) would be 20 litres x 2100, 

 say 200 hogsheads of oxygen. Feeling, no doubt, that there might 

 be difficulty in transporting and installing this amount, he adds 

 (p. 1104) that '' it would certainly be preferable to produce the 

 oxygen on the spot, ^' and says that ^^ scientific expeditions of long 

 duration to the highlands of Tibet, Ladak, and the Pamir could 

 perfectly well carry the necessary apparatus. ^^ The recent voyagers 

 in these regions do not, however, appear to have adopted Prof. 

 Bert's suggestions, and so far as I am aware they have not been 

 followed by a single mountain-traveller. 



Amongst the practical hints offered by Prof. Bert for the 

 guidance of aeronauts, who may aspire to reach great elevations, 

 there are to be found the recommendations to make '' un repas 

 d'aliments substantiels " before departure ; to eat frequently while 

 ascending ; to go slowly at great heights (that is to say, to mount 

 gradually); and, especially, ^^in order to be completely safe,"" to 

 inhale oxygen — doing so continuously when higher than 5 to 6000 

 metres (16,405-19,686 feet).^ '' If these precautions,^^ he says, '' had 

 been taken with the Zenith, there would have been no catastrophe 

 to deplore. '' 



This is a reference to the fate that befell two aeronauts (Oroce- 

 Spinelli and Sivel) who were experimented upon by Prof. Bert on 

 March 9, 1874. He shut them up in his metal cylinder and 

 reduced pressure to about the equivalent of 24,000 feet above the 

 sea. They imbibed oxygen ; noticed that the rate of their pulses 



1 Want of space obliges me to compress these directions. They will be found 

 at pp. 1094-96 of La Pression Barometrique, 



