THE WONDERFUL PROPERTIES OF BLOOD 351 



resist and combat the poison-producing microbes, and also 

 the poison itself, of all kinds, by which the race is liable 

 to be attacked. 



Few of us realise what a wonderful and exceptional 

 fluid the blood of a higher animal is. The Australian 

 natives attach so little importance to it that they actually 

 cut themselves and use their blood as a sort of paste for 

 sticking decorative feathers on to a pole ! The Papuans 

 are more advanced, since they regard the flow of blood 

 from a cut or graze as an evil portent. And some 

 respect to the greatness and wonder of blood is shown by 

 those persons among civilised peoples (more frequently 

 men than women) who faint when they see blood, or even 

 at the mention of its name ! This stream of red fluid 

 within us (of which an average man has about fifteen 

 pints in his vessels) courses at a tremendous rate from 

 the heart through all the endless branches and networks of 

 arteries, capillaries and veins, and back to the heart. It 

 feeds, cleanses, warms and takes "vital air" (the old name 

 for oxygen gas) dissolved in it to every particle of our 

 bodies, fresh and fresh at every pulse-beat as it rushes on. 

 It not only absorbs crude digested food through the walls 

 of the gut, but conveys it to where it is worked up and 

 distributes the worked-up product. It removes the quickly 

 used-up substances from every part, and the choke-damp 

 or carbonic acid which would stop the whole machine, 

 and kill us, were it not got rid of through the lungs as 

 the blood hurries through the walls of these air-sacs, whilst 

 other used-up materials are carried by it to the kidneys 

 and passed out of the body through them. Every 

 part of the body is brought into common life with every 

 other part by this impetuous blood-stream — which is here, 

 there, and everywhere, right round, and back again, in 

 twenty-five seconds ! It is obviously a very serious thing 

 if a poison-producing microbe gets into this blood-stream 



