PHYSICAL AND CHEMICAL AGENTS UPON BLOOD. 
693 
that if the ordinary respiratory act was imitated as closely as possible, by simply passing 
a current of pure atmospheric air through a series of twenty-four blown glass bulbs, 
partly filled with defibrinated arterialized ox-blood, kept in a digestive apparatus so con- 
structed as to be capable of being retained at the temperature of the human body, the 
air underwent the following change. 
Air after passing through twenty-four bulbs half filled with blood, at a temperature of 
38° C., gave the following results: — 
No. 8. — In 100 parts of air. 
Oxygen . . . 
Carbonic acid . 
Nitrogen . 
20-61) 
0-96/Total °Wn 21-57 
78-43 
It is thus seen that the blood out of the body exerts a similar chemical action upon 
air brought in contact with it as it does in the lungs of the living animal, at least so far 
as the interchange of gases is concerned. The next point being to retain the air longer 
in contact with the blood at the same temperature, the following experiment was per- 
formed. 
Defibrinated fresh ox-blood, after being well arterialized by shaking it with renewed 
portions of air, was kept during 1| hour in contact with 100 per cent, of pure atmo- 
spheric air at a temperature of 38° C. 
No. 9. — In 100 parts of air. 
Oxygen ... .19 76)^^ 0X yg en 22-68 
Carbonic acid . . 2-921 
Nitrogen . . . 77’32 
Another portion of the same blood as the preceding was heated in precisely the same 
manner, but instead of being kept only 1^ hour in contact with the air it was retained 
34 hours. 
No. 10. — In 100 parts of air. 
^ [-Total oxygen 22-87 
Oxygen. . . . 18-80 
Carbonic acid . 
Nitrogen . . . 77-13 
The effect of time is well illustrated in these three examples, for with the single 
exception of the period during which the air was in contact with the blood, all the other 
factors were identical. By placing the results in a tabular form, the influence of time is 
more easily appreciated. 
Oxygen. 
Carbonic acid. 
Nitrogen. 
Air employed 
20-96 
00-00 
79-04 
After a few seconds’ action by blood 
20-61 
00-96 
78-57 
After 1^ hour’s action 
19-76 
02-92 
77-32 
After 3^ hours’ action 
18-80 
04-28 
76-92 
