i in i-i \iri\-. \- i 



ceive thai the negative pressure would 



just ,is it racks water in ;m ordinary ball syrini i 



will, however, show thai this conclusion is untenable, parti} b< 



negath e pressure exists in the 



partly because it \\<>ul<l have to "i" >wly movii imn of 



I'l I in the thin walled veins, with the resull thai it would 



<>f thea to come together rather than produce a mov< 



blood contained in them. The negative pr< 



therefore be of much consequence in attracting I nous blood ii 



ventricle. 



Several factors maj i perati produce thi 



among which ma} be mentioned the Budden opening <>nt of the I 



the ventricles :it the beginning of diastole, the n il of I 



which hi mes compressed in the In-art walls during 



turgescence of the walls of the ventricles produced by tin* sudden inr 

 • if blood into the coronary vessels at the beginning I 



pro< tend to cause an opening oul of the walls of the venti 



a consequenl increase in the capacity of their cavitii 



The Auricular Curve 



ESxaminati f the intraauricular pressure curv< is of particular in- 



ni-<' of the relationship which it 1 a tracing tal the 



movements in the jugular vein at the ro neck n tj 



This jugular pulse curve, as it is called, is produced mainly by 

 changes of pressure occurring in the auricle, from which it <liftv 

 the relative heighl <>t" the various waves B _ iduating the intra 

 auricular pressure curve bj the method described abo 



ictly the magnitude in the changes of pr< g during 



cardiac cycle. This obvious!} can t">t be done with a tracing 

 the jugular vein, although qualitatively the tracii 

 changi ccurring in the aurich 



< >n examining the auricular pressure cun 

 finil that after the w if presystole, wl ich 



with that mi the intraventricular curve 

 in a peak aim the beginning "t" t ; 



cun e then rapidly tally ind< 



Bure, and alowlj rises throughout th. 

 tin- momenl o the auriculo 



again ami th< tr runs parallel with I 



. used to designate tin- • 

 similar wi hown "n the jugu 



