254 CIRCULATION. 



not felt in all the vessels at the same instant. By ingenious 

 contrivances, which will be described further on, this observer 

 has succeeded in registering simultaneously the impulse of 

 the heart, the pulse of the aorta, and the pulse of the femoral 

 artery. He has thus ascertained that the contraction of the 

 ventricle is anterior to the pulsation of the aorta, and the 

 pulsation of the aorta precedes the pulse in the femoral. 1 

 This only confirms the views of other physiologists, particu- 

 larly Weber, who described this progressive retardation of 

 the pulse as we recede from the heart, estimating the differ- 

 ence between the ventricular systole and the pulsation of the 

 artery in the foot, at one-seventh of a second. 2 The observa- 

 tions of M. Marey are particularly referred to as being the 

 most conclusive. 



It is evident from what we know of the variations which 

 occur in the force of the heart's action, the quantity of blood 

 in the vessels, and from the changes which may take place in 

 the caliber of the arteries, that the character of the pulse 

 must be subject to numerous variations. Many of these may 

 be appreciated simply by the sense of touch. We find wri- 

 ters treating of the soft and compressible pulse, the hard 

 pulse, the wiry pulse, the thready pulse, etc., as indicating 

 various conditions of the circulatory system. The character 

 of the pulse, aside from its frequency, has always been re- 

 garded as of great importance in disease ; and the variations 

 which occur in health form a most interesting subject for 

 physiological inquiry. 



Form of the Pulse. It is evident that few of the charac- 

 ters of a pulsation, occupying as it does but a seventieth 

 part of a minute, can be ascertained by the sense of touch 



1 MAREV, Circulation du Sang, p. 197. In an article published in the 

 Journal de la Physiologic, 1859, tome ii., p. 267, Marey took ground against 

 the progressive retardation of the pulse hi arteries removed from the heart ; but 

 hi his last work the fact is admitted, and seems proven beyond a doubt. 



2 MILXE-EDWARDS, Physiologic, tome iv., p. 188. 



