THE EFFECT OF CHANGE OF POSTURE 



201 



FIG. 104. THE EFFECT OF ADMINISTRATION OF CHLOROFORM UPON THE HEART 

 VOLUME (CARDIOMETER) AND ARTERIAL PRESSURE OF A DECEREBRATE DOG : 

 TIME IN SECONDS. (Dixon.) 



3 to 4 per cent. Chloroform administered during period A. Systole (downstroke) 

 becomes progressively weaker and cardiac tonus is diminished, so that the heart 

 becomes distended with blood, only a small proportion of which is expelled during 

 systole. The fall in blood-pressure is due to this effect; as the cardiac systole 

 improves the blood-pressure rises. 



FIG. 105. SAME AS FIG. 104, BUT NEARLY PURE ETHER ADMINISTERED. (Dixon. 



The systolic contractions are weakened, bv.t the effect is less serious than with chloro- 

 form, and the fall in blood -pressure less. 



