io6 



TIME-RELATIONS OF THE MOVEMENTS OF THE HEART. 



Gibson had the opportunity of taking cardiograms from a case of fissure of 

 the sternum in a man, and obta'ined the following: time-values: Auricular contrac- 

 tion (a b) =0.115, ventricular contraction (b d) =0.28, interval between the 

 closure of the valves (d e) = 0.09, ventricular diastole (e f) = o.u, pause = 0.45 

 second. 



In large mammals (horses) Marey and Chauveau, in 1861, by a most 

 thorough method obtained records of the phases of the movements of the heart 

 in the following manner: Long catheter-like tubes, provided at their lower ex- 

 tremity with a closed and compressible rubber bulb, were connected by means of 

 a flexible piece of tubing attached to the other end with the registering drum of 

 the cardiograph (Fig. 44, KS). It is evident that with every compression of the 



Aorta. 



Apex 

 of the 

 Heart. 



FIG. 31. Curves Showing the Movements of the Separate Portions of the Heart (Chauveau and Marey). 



rubber bulb the stylus connected with the registering drum of the instrument will 

 be elevated. 



Fig. 31 shows a number of curves: In making A the rubber bulb was in the 

 right auricle, having been introduced through the jugular vein and the superior 

 vena cava; in making B the bulb was introduced into the right ventricle through 

 the tricuspid orifice; in making D it was introduced through the carotid as far 

 as the root of the aorta; in making C, through the semilunar valves of the aorta 

 into the left ventricle; and, finally, in making E the bulb was applied externally 

 to the apex of the heart between this and the inner aspect of the chest-wall. In 

 all of the curves v indicates the auricular contraction, V the ventricular contrac- 

 tion, s the closure of the semilunar valves (which occurred earlier in B than in C), 

 and P the pause. As the recording surface moves at a uniform rate and the 



