290 



PRACTICAL PHYSIOLOGY. 



[LX. 



(a.) Adjust the tambour (B) over the cardiac impulse, and fix the bag (A) 

 on the abdomen so as to record simultaneously the cardiac impulse and the 

 respirations (fig. 210). The experimenter may also take a tracing of the 

 cardiac impulse while the respiration is arrested. 



FIG. 212. P. Tracing of radial pulse; /'. Eespirations; T. Time in seconds. 



(b.) Take a tracing of the radial pulse and the respiratory movements. 

 Fig. 211 shows how the receiving tambour is adjusted over an artery. At 

 the same time record the respirations, and note in the tracing (fig. 212) how 



FIG. 213. P. Tracing of the radial pulse ; H. Of the cardiac impulse; 

 T. Time in seconds. 



the number and form of the pulse-beats vary during inspiration and expira- 

 tion the number being greater during inspiration. 



(c.) Take a tracing of the radial pulse and the cardiac impulse simultane- 

 ously (fig. 213). 



