HYDE: EXPERIMENTS ON THE SKATE. 



55 



Curve 41. Effect of m% NH4CI. 



Cxirvo 41. 



Upper, Hiirthle cardiac and blood pressure show a decrease in cardiac 

 activity and blood pressure. Lower, i-espiratory curve; for fifteen min- 

 utes prolonged expiratory phase and irregular rhythm, then weak but 

 regular. 



Effects of dehydrated chemically pure Na2S04 solutions are 

 most pronounced in the strong concentration of m/2 and m/1, 

 both of which increase the force of cardiac, respiratory and 

 blood-pressure activities, leaving the rate unchanged. The 

 effect lasts longer with the weaker solution, and the after- 

 effects are not, as with the saturated m/1 solution, a weaken- 

 ing of the rhythm and fall in pressure. 



Table XI. Summary of NajS04 effects on respiratory cardiac, and blood- 

 pressure changes. 



Curve 42. Effect of m/64 Na2S04. 



carve 42. 



Upper, Hiirthle cardiac and blood-pressure curve, and lower, respira- 

 tory, all show no change after injection of the solution. 



Curve 43. Effect of m/2 Na2S04. 



Corra 43. 



