9 6 4 



HANDBOOK OF PHYSIOLOGY 



CIRCULATION II 



FIG. 2.1. Diagram of apparatus for measuring capillary blood pressure directly. Micro- 

 pipette shown before introduction {upper left) and in capillary [after introduction {lower left). 

 [From Landis (198).] 



fig. 2.2. Curve showing aver- 

 age gradient of pressure through 

 the mesenteric blood vessels of 

 the frog. [From Landis (198).] 



8 10 



LENGTH 



12 

 MM 



30 

 25 

 20 

 15 

 10 



- 5 



18 20 



was also a significant drop in the capillaries, amount- 

 ing on the average, with ordinary blood flows, to 20 

 or 30 per cent of the total (198). A somewhat smaller 

 gradient was also calculated from Poiseuille's equa- 



tion and motion picture analyses of flow through 

 capillary networks (206). 



The same determinations provided direct support 

 for the Starling filtration-absorption hypothesis. 



