232 



Chapter XV 



of the diet as on normal days since the curve remained mesectic. 

 How then was the carbonic acid got rid of? If the same quantity of 

 C0 2 was produced on the days of diet as on the days of rest, and if 

 also the C0 2 in the alveolar air was less than normal, it would appear 

 that the CO. 2 produced was diluted with a greater quantity of atmo- 

 spheric air than usual, which would be another way of saying that 

 the ventilation was increased, a deduction which seems to be incon- 

 sistent with our original statement, for it would involve stimulation 

 of the respiratory centre and meionexy. The other possibility would 

 be that the actual C0 2 production went down. 



In a later experiment which yielded similar data as regards the 

 dissociation curve, the rate of respiration and the total ventilation 

 were measured. There was no very obvious increase on the 8th and 

 9th of November, the days of diet on which the dissociation curve 

 data were obtained, as compared with the 4th of November. 



At the end of the period of diet there is an evident tendency for 

 the total C0 2 output to fall. The point is not one of great import- 

 ance in the present connection, but with a greater degree of acidosis 

 it is clear that dyspnoea, such as takes place in diabetes, must 

 supervene a definite dyspnoea prompted by the effects of oxybutyric 

 acid &c. on the respiratory centre. Here, however, I wish merely 

 to indicate to the reader the nature of the problems in which he 

 is likely to involve himself if he uses the dissociation curve as an 

 " indicator." 



The last point which must be considered is the degree of acidosis 

 which took place. Here let me repeat that I mean by this phrase 

 the degree to which acids other than C0 2 were added to the blood, 

 assuming the bases to remain constant. This point was tested in 

 another experiment ; in it also the blood remained mesectic through- 

 out the dietetic period, i.e. it gave the same dissociation curve when 



