CIRCULATION OF THE BLOOD. 



ter of the flow from the venous end of the schema. Is it continuous, 

 remittent, or intermittent? Note also the excursions of the col- 

 umn of mercury in each manometer. Is there any difference in 

 pressure as indicated by the two manometers ? Explain. 



Increase the peripheral resistance by tightening one of the cap- 

 illary damps. Repeat the intermittent pressure on the syringe 

 bulb. Has the character of the flow changed ? Compare the two 

 manometers. Is there any change in arterial pressure as com- 

 pared with venous pressure? Is the fall in arterial UMamic be- 

 tween the strokes of the pump large or small? Does the venous 

 pressure still rise and fall with the heart-beat ? FTplam. 



Increase the peripheral resistance still more by tightening more 

 clamps. Note the change in arterial pressure as compared with 

 venous pressure, during the series of pump strokes. Note the 

 change in the character of the outflow of fluid from the veins and 

 the speed of flow as compared with the speed with lower resistance. 

 Does the flow continue after the pump has ceased to act? Does 

 the arterial pressure fall more slowly or more rapidly than before? 



Is the excursion of the column of mercury in the arterial manom- 

 eter greater or less with each pump stroke dm before? 



Decrease the rate of pump strokes. What is die effect on blood 

 flow and on arterial pressure? 



Dilate the arterioles by loosening a damp. Using the same rate 

 of pump strokes as before and as nearly as possible the same 

 strength of stroke, what is the effect on arterial pressure and on 

 venous flow? 



Record of Pulse in Artificial Schema. Close the damps on the 

 tubes representing the capillary drculation until, with freqeunt 

 regular compressions of the pump, a constant outflow from the 

 reins is obtained and die asdOatiaas of die arterial mannmetfr 

 are slight. Determine the mean arterial pressure by multiplying 

 the height of the column of mercury in the distal limb of the manom- 

 eter above the meniscus in the proximal limb by 2. 



Clamp off the immaaHH from die artery tube. On the artery 

 near the bulb adjust a receiving tambour. Connect this with a re- 



