The effect of diet on the dissociation curve of blood 233 



exposed to the C0 2 pressure of the alveolar air at the time the blood 

 was drawn. Before the diet the alveolar C0 2 was 37 mm., on the diet 

 31 mm. What degree of acidosis compensated for these 6 mm. of CO 2 ? 

 This could be directly found by using the dissociation curve of the 

 blood without any CO 2 present as an indicator. The curve was the 

 same as that of normal blood to which was added 0*03 % lactic acid, 

 but no doubt the actual acids present were yS-oxybutyric and others 

 found in the urine. 



In getting a clear understanding of the distinction between blood- 

 acidosis and meionexy, as I use the phrases, the reader may find the 

 following figure useful, though it pretends to no quantitative accuracy 



CO 2 mm 

 30 



40 



10 - 



I II HI W IT 

 FIG. 111. Scheme illustrating the relation between C0 2 pressure in alveolar air and 

 blood, acidosis and A'. The figures in this are purely hypothetical, they do not 

 correspond to the blood of any actual person. 



and it takes many things for granted, such as the constancy of the 

 bases present. He may get a conception of the acids which rise and 

 fall in blood as the "floating" acids they consist of C0 2 and organic 

 acids, lactic, /3-oxybutyric, diacetic, &c. 



Consider samples of blood I, III, V and VII. The alveolar CO, 

 decreases progressively from I VII. The added organic acids, repre- 

 sented by the black area, increase progressively from I VII, but the 



