Heart and Blood 71 



Seeing, therefore, that the moderately tight ligature 

 renders the veins turgid, and the whole hand full of 

 blood, I ask, whence is this ? Does the blood accu- 

 mulate below the ligature coming through the veins, or 

 through the arteries, or passing by certain secret pores ? 

 Through the veins it cannot come ; still less can it 

 come by any system of invisible pores ; it must needs 

 arrive by the arteries, then, in conformity with all that 

 has been already said. That it cannot flow in by the 

 veins appears plainly enough from the fact that the 

 blood cannot be forced towards the heart unless, 

 the ligature be removed ; when on a sudden all the- 

 veins collapse, and disgorge themselves of their contents, 

 into the superior parts, the hand at the same time 

 resuming its natural pale colour the tumefaction and 

 the stagnating blood have disappeared. 



Moreover, he whose arm or wrist has thus been 

 bound for some little time with the medium bandage, 

 so that it has not only got swollen and livid but cold, 

 when the fillet is undone is aware of something cold 

 making its way upwards along with the returning blood, 

 and reaching the elbow or the axilla. And I have 

 myself been inclined to think that this cold blood 

 rising upward to the heart was the cause of the fainting 

 that often occurs after blood-letting : fainting frequently 

 supervenes even in robust subjects, and mostly at the 

 moment of undoing the fillet, as the vulgar say, from 

 the turning of the blood. 



Farther, when we see the veins below the ligature 

 instantly swell up and become gorged, when from 

 extreme tightness it is somewhat relaxed, the arteries 

 meantime continuing unaffected, this is an obvious 

 indication that the blood passes from the arteries into 

 the veins, and not from the veins into the arteries, and 

 that there is either an anastomosis of the two orders of 

 vessels, or pores in the flesh and solid parts generally 

 that are permeable to the blood. It is farther an 

 indication that the veins have frequent communications 



