244 



ENDOCARDIAC PRESSURE. 



[BOOK i. 



a' 



FIG. 40. 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. 41. THE MEMBRANE-MANOMETER OF HtiBTHLB 1 . 



i For this figure I am indebted to Mr Albrecht, the University Instrument- 

 maker at Tubingen. 



