1894.] Injection of Sugar on the Gases of the Blood. 15B 



Having now briefly given the results met with in each separate 

 experiment, I will now consider the results as a whole. 



In the first place, we see there was a decrease in the quantity of 

 carbonic acid in all the different specimens of blood during the first 

 hour after the sugar was injected, the diminutions being 10*374, 

 10-499, 9-185, and 7*380 per cent. 



In the second place, the blood, taken five hours after the sugar was 

 injected, showed a decrease of 3-023 and 9'615 per cent, (in Experi- 

 ments 1 and 2) ; while after three hours there was a decrease of 

 4'260 per cent, (in Experiment 3). In all the three cases it had 

 therefore shown, during the later hours, a more or less marked 

 tendency to return to the normal amount. In Experiment 4 the 

 blood at the third hour contained 14' 795 per cent, less carbonic acid 

 than the normal blood, and 4*415 per cent, less than what it con- 

 tained at the first hour. This discrepancy may be due to the fact 

 that a greater percentage of sugar was injected, and the dog was in 

 consequence rendered more comatose. This view seems the more 

 likely, as in Experiment 2, when the dog was semi-comatose, the 

 carbonic acid was markedly diminished at the fifth hour.* 



These united results support the view that the lactic acid derived 

 from the splitting up of the sugar in the animal body drives off 

 the carbonic acid from the sodium salts and replaces it. This view 

 is still further supported by the fact that the quantity of carbonic 

 acid in the blood withdrawn at the different periods after the sugar 

 injection, varied in the same manner as the quantity of lactic acid 

 had been found to do. In both cases during the first hour after 

 the sugar injection, one finds larger quantities than during the later 

 hours. 



Whether the percentage decrease in the amount of the carbonic 

 acid hinders its elimination by the lungs or not will depend upon 

 how much power the combined lactic acid has of hindering the blood 

 from taking up the carbonic acid from the tissues and the tension of 

 the existing gas. 



This point would be ascertained by estimating the quantity of 

 carbonic acid expired after the sugar injection. The experiments I 

 have already published! on this point show that there is no decrease 



the amount of carbonic acid expired from an animal immediately 

 Eter sugar has been injected into its circulation. In fact there was 

 an actual increase of carbonic acid in all but one casej during the 

 irst hour. 



" Small dogs," as I stated in my former paper, " are relatively much more sus- 

 ceptible than large ones to the effect of sugar injection." 



t Vaughan Harley, " Influence of Sugar in the Circulation on the Respiratory 

 Oases," ' Journal of Physiol.,' vol. 15, p. 139, 1893. 

 Ibid., Exp. 9, p. 147. 



