82 Mr J. 0. Adami, On the action of the [May 12, 



as to the automatic, non-nervous action of cardiac muscle-fibres. 

 No nerve ganglia, and, as far as we know, no nerve fibres have 

 been made out as controlling the musculi papillares, and the 

 moment at which they begin to contract, the duration, and the 

 extent of their contraction would appear to be determined in large 

 measure by the intraventricular blood pressure and the quality of 

 the blood. 



In conclusion, a few words may be said as to the way in which 

 our observations throw light upon certain peculiarities of the 

 pulse curve, which so far have been very variously explained — 

 and as to which there has been much uncertainty. In tracings of 

 the normal pulse gained by Marey's sphygmograph, or the equally 

 unsatisfactory modification thereof usually employed in this 

 country, or again by Dudgeon's sphygmograph in what may be 

 termed its lucid intervals, there can often be seen two well- 

 marked secondary waves in the first part of the curve previous 

 to the dicrotic notch. The first of these has received the name of 

 'apex' or 'percussion' wave, the second that of 'tidal' or 'pre- 

 dicrotic.' That the former is not simply due to inertia is shewn 

 by the fact that not unfrequently a small inertia wave may be 

 superposed upon it, removable by proper adjustment of the instru- 

 ment. By comparing the curves of the contraction of the ven- 

 tricular wall or of the intraventricular blood pressure with the 

 pulse curve taken simultaneously at the base of the aorta, Professor 

 Roy and I have been enabled to shew that the first of these curves 

 corresponds in time to the first period of contraction of the papillary 

 muscles and the consequent increase in the intra-cardiac (and 

 intra-arterial) blood pressure. This should therefore be termed 

 the papillary wave. The second we consider is not by any means 

 a secondary wave, but is really the latter portion of main wave due 

 to the general ventricular systole, the first smaller papillary wave 

 being superposed upon its first portion. This we would call the 

 systole remainder ivave, or, more shortly, remainder wave. 



The same series of observations has also given us an explana- 

 tion of the form of pulse usually termed the anacrotic, in which 

 there is a small well-marked wave upon the upstroke of the pulse 

 tracing, not, as in normal conditions, forming tbe apex of the curve. 

 This form is to be found in cases where there is high intra-arterial 

 pressure, or obstruction to the onward flow of the blood. Where 

 there is high intra-arterial pressure there also the intra-cardiac 

 pressure must be raised to a correspondingly high point before it 

 becomes greater than that in the aorta, and before the valves be 

 thrown open, that is to say, the pulse wave must begin at a later 

 period of the cardiac systole. I have already stated that there is 

 no absolute relation between commencement of the papillary 

 contraction and the moment of opening of the aortic valves. 



