194 



ENDOCAKDIAC PKESiSUKE. 



[BooK i. 



FIG. 39. CURVES OF ENDOCARDIAC PRESSURE. FROM LEFT VENTRICLE OF DOG. 

 (Roy and Rolleston.) 



A. a quickly beating, B. a more slowly beating heart. 



An instrument which has been much used of late, and the use 

 of which has given very valuable results is the " membrane-mano- 

 meter" of Hiirthle. 



FIG. 40. THE MEMBRANE-MANOMETER OF HuRTHLE. 1 



1 For this figure I am indebted to Mr. Albrecht, the University Instrumer 

 maker at Tubingen. , 



