Symptoms of Decompression 



707 



11:44; 420 mm.; impossible to whistle; the bird is still very sick, 

 crouching on its perch. 



11:46; 480 mm.; impossible to whistle. 



11:47; 550 mm.; still impossible to whistle; pulse, 66. 



11:48; 580 mm.; I can whistle the low notes, but not the high ones. 



11:49; 630 mm.; I can whistle very well. 



11:51; returned to normal pressure; pulse, only 52. The rectal 

 temperature of the sparrow is 36.1°; that of the rat, 34°; my tempera- 

 ture under the tongue is 36.5°. 



At 3:30, the sparrow's rectal temperature is still only 38.7°. 



Here is an experiment in which in an hour and a quarter I 

 reached a minimum pressure of 248 millimeters, that is, less than a 

 third of normal pressure, during which experiment I remained 45 

 minutes below 400 millimeters, without having experienced dis- 

 comfort from the moment when I began to breathe the super- 

 oxygenated air regularly. My pulse, as the lower graph in Figure 

 59 shows, remained from then on at its normal figure; it even 

 dropped towards the end, either because of the long rest in a 

 seated posture, or under the influence of breathing superoxy- 

 genated air. Beside me, a sparrow and a rat were very sick, and 



Fig. 59 — Modifications in the pulse rate, during decompression, by contin- 

 uous breathing of oxygen. (Exper. CCLVII.) 



