376 RESPIRATION 



of the rope with his teeth, and so succeeded in opening the valve 

 and turning the balloon downwards. By his presence of mind 

 and determination he saved both Glaisher's life and his own. 



The next very high ascent was made by the three French sci- 

 entists Croce-Spinelli, Sivel, and Tissandier in 1875, and re- 

 sulted in the death of the two former. This tragic occurrence 

 revealed in a very clear manner the insidiousness of the onset of 

 dangerous anoxaemia, and the absolute necessity for taking the 

 most efficient means of guarding against it at very high altitudes. 

 Croce-Spinelli and Sivel had tried the effects of oxygen in Paul 

 Bert's steel chamber, as well as during a previous ascent to about 

 25,000 feet. They were thus familiar with its effects. The balloon 

 was therefore provided with bags of oxygen. Paul Bert, who was 

 away from Paris at the time, had, however, written to them that 

 the bags provided were too small to last for more than a short 

 period. There was not time, however, to get larger ones, and for 

 this reason they decided not to begin using the oxygen till they 

 felt themselves really in need of it. They reached a height of 

 about 24,600 feet with the barometer at 300 mm. and the balloon 

 no longer rising. At this point Sivel asked both his companions 

 whether they would go higher, and on receiving their assent cut 

 the strings of three bags of sand used as ballast. Figure 99 repre- 

 sents the appearance of the car of the balloon at this point. In 

 Tissandier's notebook there was the entry "1.25, T = — 10°, 

 B = 300. Sivel throws ballast. Sivel throws ballast." The writing 

 was scarcely legible, and the repetition of the words was charac- 

 teristic of the symptoms of anoxaemia. The balloon then rose 

 rapidly. Tissandier relates that he tried to take up the mouthpiece 

 of the oxygen tube, but his arms would not move. Nevertheless 

 he had no sense of the danger, but felt happy that they were 

 rising. He saw the barometer passing 290 and then 280 and wished 

 to call out that they were at 8,000 meters, but his voice was 

 paralyzed, and immediately afterwards he lost consciousness and 

 did not wake up till about forty minutes later. 



The balloon was then descending rapidly and he noted that 

 the barometer was at 315. His companions were still unconscious. 

 He let go some ballast, and shortly afterwards Croce-Spinelli 

 woke up and let go more, including the aspirator. He then became 

 unconscious again. The balloon must have gone up, and he did 

 not wake up again till an hour and a quarter later. The balloon 

 was then at about 20,000 feet and falling very rapidly. Both Sivel 

 and Croce-Spinelli were dead. Tissandier had great difficulty in 



