296 THE SNAKES OF SOUTH AFRICA. 
THE ELIXIR OF LIFE. 
Connected with the heart is an endless system of tubes, 
which carry the blood all over the body. 
The blood is the elixir of life. The stomach, with the aid 
of the liver, pancreas, bowels, and lungs, changes the food 
which we eat into blood, in a most marvellous way. The blood 
is composed of tiny bodies, known as corpuscles and a watery 
fluid known as Liquor Sanguinis. There are red, and there are 
Fic. 122.—Exterior view of the human heart and the great 
blood vessels. The heart has four chambers—two auricles 
and two ventricles. (From Blackie’s Physiology.) 
white corpuscles. The red corpuscles are those which make 
the blood appear red. They and the Liquor Sanguinis carry 
food to every cell of the body. In fact, they are living food— 
the elixir of life. They renew the wasted cells. They are the 
builders. As quickly as the cells of the body are broken down, 
so they build up more. The white blood corpuscles are also 
known as Phagocytes or Leucocytes. They attack and eat up 
disease microbes, and repair wounds. 
