352 



PEACTICAL PHYSIOLOGY 



artery. The tambour is connected by means of a i-tube with a 

 recording tambour. 



Fio. 233. Tambour-sphygmographs arranged for measuring the velocity of trans- 

 mission of pulse-wave. 



The writing styles of the carotid and impulse tambours are arranged 

 to write exactly beneath one another. A time tracing is taken beneath 

 the curves. The beginning of the impulse curve marks the beginning 



FIG. 234. Impulse (I.) and pulse curves (II.). The vertical lines, marking the 

 ascent of the pulse curve and the dicrotic notch, indicate the opening and closing of 

 the semi-lunar valves. 



of the ventricular contraction. The beginning of the carotid pulse curve 

 marks the beginning of the period of systolic output and the opening 

 of the aortic valves Between these points is the period of rising 



