186 Influence of Resilience of Arterial Wall on Blood-Pressure. 



veins, the whole gland feeling tense to the touch. Increased hardness of 

 the arteries, supplying such an active organ, permits the full force of the 

 systolic wave to come into play, and insures a flow of blood in the face of the 

 increased osmotic pressure and swelling of the tissues. 



Tn the condition of local inflammation the heart beats forcibly, and the 

 arteries conduct the full force of the wave to the swollen, tense, inflamed 

 part ; the part throbs with pain. A fomentation, by softening the arteries 

 and the confining frameworks which surround the tissue cells, or the surgeon's 

 knife by relieving the tension, permits an ampler flow of blood with its 

 curative properties. 



It is the altered osmotic condition of the infected inflamed tissue which 

 causes the swelling, and this may advance to such a degree that the circula- 

 tion is strangled and the part necrosed ; before this happens, however, the 

 full stroke of the heart's systole is conveyed by the hard contracted arteries 

 with hammer-like strokes to the part and forces the blood through the 

 vessels, maintaining the circulation and thus allowing the bacterial poisons to 

 be neutralised up to the utmost possible limit. Probably the hypertrophy of 

 the muscular coat of the arteries in certain pathological conditions is 

 correlated with a need for the hammer-like stroke. 



