Gases of the Blood 601 



pressure 22 cm.). Drew from the same artery 40 cc. of blood, very 

 dark . . . . B 



Blood A (76 cm.) contains per 100 volumes: O 21.5; CO 41.9. 



Blood B (22 cm.) contains per 100 volumes: O 10.7; CO 22.0. 



50 per cent of the oxygen has disappeared and 47.5 per cent of 

 the original carbonic acid. 



Experiment CLXV. June 28. Pressure 76 cm.; temperature 21.8°. 

 Dog of the preceding experiment, quite recovered, vigorous. 



While ligating the left carotid in preparation, the femoral ligated 

 three days before opens, and blood issues; the animal thus loses about 

 50 cc. of blood. 



Then put into the apparatus, pressure is lowered 19 cm. in 5 

 minutes (real pressure 57 cm.); left there for a half hour. Then 42.3 

 cc. of blood drawn from the left carotid, not very red .... A 



The animal, brought back to normal pressure, breathes quietly 

 for an hour. Then 42.3 cc. of blood drawn from the same carotid; 

 evidently redder . . . . B 



Blood A (57 cm.) contains per 100 volumes: O 18.6; CO^ 35.4. 



Blood B (76 cm.) contains per 100 volumes: 0^> 21.6; CO 36.3. 



Experiment CLXVI. July 4. Pressure 76 cm.; temperature 22°. 

 Female dog of moderate size. 



At 3 o'clock, 45.3 cc. of blood, not very red, drawn from a 

 femoral .... A 



Animal put into apparatus; howls and is very uneasy; pressure 

 lowered 52 cm.; then 47 cm.; then 50 cm.; all in about a quarter of an 

 hour. The real pressure is 26 cm. 43.1 cc. of very dark blood then 

 drawn from the same artery . . . . B 



Blood A (76 cm.) contains per 100 volumes: O 18.3; CO 32.8. 



Blood B (26 cm.) contains per 100 volumes: O^ 9.8; CO 24.5. 



Experiment CLXVII. July 6. Pressure 76 cm.; temperature 24.5°. 

 Dog of the preceding experiment, in good condition. 



Put into the large apparatus; in a quarter of an hour brought to 

 44 cm. of actual pressure; very uneasy; kept at this pressure for 20 

 minutes, and then 32.6 cc. of rather dark blood drawn from the left 

 carotid .... A 



The animal having been brought back to normal pressure, which 

 took about 5 minutes, 42.3 cc. of blood, evidently redder, were drawn 

 from the left carotid immediately . . . . B 



Blood A (44 cm.) contains per 100 volumes: O 16.3; CO 23.3. 



Blood B (76 cm.) contains per 100 volumes: O* 19.8; CO 29.1. 



Experiment CLXVIII. July 8. Pressure 75.9 cm.; temperature 25°. 

 Very large dog. 



Put into the apparatus; has a new cannula of Model A (Fig. 29) in 

 the left carotid. Pressure lowered 20 cm. in a quarter of an hour, and 

 left there a quarter of an hour. 39 cc. of blood then drawn with 

 difficulty .... A 



Pressure lowered 30 cm., and an attempt is made to extract blood; 

 but it is impossible, the cannula is twisted. 



