HYDE: EXPERIMENTS ON THE SKATE. 



47 



The effects of Na2C0.{ injections are tabulated in table V. 

 It was observed that Na2C03 solutions are most effective in 

 strengthening the force of the cardiac rhythm and thus rais- 

 ing the blood pressure. They do not stimulate respiratory 

 activity except in strong doses, when they may increase the 

 force. Its pronounced influence upon the heart may be due to 

 OH ions that are set free by the dissociation. 



Curve 24. Effect of Na2C03 m/32. 



Ouna 24. 



rv^lVv^^/^^v^^r\^^^^ 



Upper curves, cardiac and blood pressure with Hiirthle. Rate un- 

 changed, force and blood pressure increased. Lower, respiratory; force 

 and rate unchanged. Time, five seconds. 



Curve 25. Na2C03 m/8. 



^^^^JMV^f^^^^^r^^^r^^^r^ 



Upper curves, cardiac and blood pressure. Rate decreased, force 

 greatly increased, pressure rose. Lower curve, respiratory ; force and rate 

 unchanged. Time, five seconds. 



