PULSE 



55 



row, etc. We feel the pulse to learn several things: (i) 

 Its frequency, which tells how many times the heart is beat- 

 ing. 



(2) Its tension, which is the state of the arterial walls 



FIG. 30. Portion of the wall of ventricle. 



d, d', and aorta, a, b, c, showing attachments of one flap of mitral and the 

 aortic valves; h and g, papillary muscles; e, e' and f, attachment of the tendi- 

 nous cords. (From Yeo after Allen Thompson.) 



and is the resistance offered in peripheral vessels. We 

 judge the tension by the force necessary to obliterate the 

 impulse. 



