CIRCULATION OF THE BLOOD 113 



to the body at large and sending it into the veins; re- 

 ceiving none from the lungs, however, they are soon ex- 

 hausted, and left, as it were, empty. But even this fact 

 confirms our views, in no trifling manner, seeing that 

 it can be ascribed to no other than the cause we have 

 just assumed. 



Moreover, it appears from this that the more frequently 

 or forcibly the arteries pulsate, the more speedily will the 

 body be exhausted of its blood during hemorrhage. Hence, 

 also, it happens, that in fainting fits and in states of 

 alarm, when the heart beats more languidly and less forcibly, 

 hemorrhages are diminished and arrested. 



Still further, it is from this, that after death, when 

 the heart has ceased to beat, it is impossible, by dividing 

 either the jugular or femoral veins and arteries, by any 

 effort, to force out more than one-half of the whole mass 

 of the blood. Neither could the butchers ever bleed the 

 carcass effectually did he neglect to cut the throat of the 

 ox which he has knocked on the head and stunned, before 

 the heart had ceased beating. 



Finally, we are now in a condition to suspect where- 

 fore it is that no one has yet said anything to the purpose 

 upon the anastomosis of the veins and arteries, either 

 as to where or how it is effected, or for what purpose. 

 I now enter upon the investigation of the subject. 



CHAPTER X 



THE FIRST POSITION : OF THE QUANTITY OF BLOOD PASSING 

 FROM THE VEINS TO THE ARTERIES. AND THAT THERE IS 

 A CIRCUIT OF THE BLOOD, FREED FROM OBJECTIONS, AND 

 FARTHER CONFIRMED BY EXPERIMENT 



So far our first position is confirmed, whether the thing 

 be referred to calculation or to experiment and dissection, 

 viz., that the blood is incessantly poured into the arteries 

 in larger quantities than it can be supplied by the food; 

 so that the whole passing over in a short space of time, 

 it is matter of necessity that the blood perform a circuit, 

 that it return to whence it set out. 



