4. The amount of lymph is proportionate to the rise of the mean 

 arterial and capillary pressures, and these pressures have been 

 found to follow exactly the same prolonged rhythmical course 

 after the ingestion of food, as does the effusion of lymph. 



The following example shows the agreement between the blood- 

 pressures and the amount of lymph :- 



Percentage Mean arterial 



of lymph. pressure. 



Before the meal None 100 c.mm. Hg. 



i hour after. 10 110 



1 hour after 16 116 ,, 



1J hours after 8 108 



2 hours after 5 105 



3 hours after None 100 



The method devised for observing the capillary pressure is not quite 

 so delicate for the smaller variations as I could wish, and I am hoping 

 to improve it ; but it is sufficiently definite to show that the capillary 

 blood-pressure is raised throughout the digestive circulatory disturbance, 

 and especially so at the acme of it, and falls again at the close of it. 

 When the mean arterial pressure is 100 cmm. Hg. before a meal, as in 

 the above example, the capillary blood-pressure will read, 20 cmm. 

 Hg. ; and in an hour after the meal, when the arterial pressure rises 

 to 115 cmm. Hg., or so, the capillary pressure will rise to at least 

 30 cmm Hg. Though this is a large relative rise, my observations 

 show that it is not less than this, and that it is often more. 



