THE CIRCULATION 



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B 



D 



FIG. 15. 



A, A cardiogram, or tracing of the impulse of the heart, recorded on a blackened plate borne 

 on the end of a vibrating tuning-fork ; a 6, the systole of the auricles ; b e, the ventricular 

 systole. From c e the heart is shrinking as blood leaves it by the aorta and pulmonary 

 artery. B, C, D, B, F, Sphygmograms. B is shaded to show the portion of the pulse- 

 wave which corresponds to the systole of the heart. C, High-tension pulse of vigorous 

 health. D, Low-tension pulse. E, Dicrotic pulse of fever. F, Hog-backed pulse of 

 hardened (atheromatous) arteries. 



