320 



THE BLOOD AND ITS CIRCULATION 



will be drawn away to the brain, leaving the digestive tract with an in- 

 sufficient supply. Indigestion may follow as a result. 



The Effect of Exercise on the Circulation. — It is a fact familiar 

 to all that the heart beats more violently and quickly when we are 

 doing hard work than when we are resting. Count your own pulse 

 when sitting quietly, and then again after some brisk exercise in the 

 gymnasium. Exercise in moderation is of undoubted value, be- 

 cause it sends the increased amount of blood to such parts of the 

 body where increased oxidation has been taking place as the result 

 of the exercise. The best forms of exercise are those which give 

 as many muscles as possible work — walking, out-of-door sports, 

 any exercise that is not violent. Exercise should not be attempted 

 immediately after eating, as this causes a withdrawal of blood from 

 the digestive tract to the muscles of the body. Neither should 

 exercise be continued after becoming tired, as poisons are then 

 formed in the muscles, which cause the feeling we call fatigue. 

 Remember that extra work given to the heart by extreme exercise 

 may injure it, causing possible trouble with the valves. 



Treatment of Cuts and 

 Bruises. — Blood which oozes 

 slowly from a cut will usually 

 stop flowing by the natural 

 means of the formation of a 

 clot. A cut or bruise should, 

 however, be washed in a weak 

 solution of carbolic acid or 

 some other antiseptic in order 

 to prevent bacteria from ob- 

 taining a foothold on the ex- 

 posed flesh. If blood, issuing 

 from a wound, gushes in dis- 

 tinct pulsations, then we know 

 that an artery has been sev- 

 ered. To prevent the flow of 

 blood, a tight bandage known 



Stopping flow of blood from an artery by tmirmnupt mimt hp tied 



applying a tight bandage (ligature) be- ^^ ^ lOUrmquei muSI DC Ilea 



tween the cut and the heart. between the cut and the heart. 



