Tlie Measurement of Arterial Pressure in Man. 531 



Experiment IX. 



The following was an experiment in which the result is to be explained 

 on the same lines. 



The flow was through the artery and the tissue schema placed in series 

 and each in a separate compression chamber. These chambers were con- 

 nected with each other and with the pressure bottle. 



The tube connecting the artery with the tissue schema was connected 

 with the manometer. The compression was raised until the artery flattened 

 in diastole and the manometer gave maximal swings. On closing the tube 

 leading to the compression chamber of the tissue schema the artery flattened 

 to a greater extent and the pulse amplitude became diminished (Sg. 16). 

 The explanation is as follows : — 



The tissue schema then became a rigid structure and no longer stored the 



Fig. 16. 



systolic force. Therefore the diastolic pressure in the artery diminished 

 and the artery was more effectually closed by the compression during 

 diastole. The systole in its turn was less effectual in driving fluid through 

 the artery. The systolic force was spent more on the lability of the artery, 

 i.e., in opening it out. 



Like results were obtained when we substituted the kidney for the tissue 

 schema. 



When the chamber containing the artery was closed in place of that 



vol. lxxxviii. — B. 



Fig. 17. 



