48 



Chapter IV 



that by finding out what discrepancies still existed, to shed some light 

 on the factors which remained for investigation. Great then was our 

 excitement and delight when we found that point after point on the 

 curve of human blood lay also on the curve of the haemoglobin 



100 



120 



130 



140 



150 



160 



80 



90 



100 



FIG. 25. Ordinate = percentage saturation. Abscissa = tension of 2 in mm. of mercury. 



Dissociation curve of human blood at 40 mm. tension of CO 2 . = determination for 

 human blood. o = ditto for haemoglobin solution with salts of human red blood 

 corpuscles. The area drawn round the point is the experimental error in each case. 

 Temperature 37 38 C. More recent observations have shown that the portion of 

 the curve below 15mm. pressure, while traversing the shaded areas, approaches the 

 base line more gradually. 



solution (a), whilst the corresponding points for dog's blood adhered 

 with equal fidelity to the curve obtained from solution (6). The 

 points in question are also given in the figure, and the reader will 

 observe that only in one point on each curve does there seem to be 



