HOW WE POISON OUR BLOOD. 299 
which can only breed in your throat, when your blood is 
impure. 
A REMARKABLE CHANGE. 
When the oxygen has combined with the poisons in the 
blood and removed them in the form of carbonic acid gas, the 
blood, instead of being a purplish colour, is now bright red. It 
has been changed from venous blood, to arterial blood. It is 
now pure again, loaded with oxygen. The tiny blood vessels 
gradually merge one into another, like a multitude of little rivulets 
running together. Larger and larger become the vessels or tubes, 
until they all merge into great channels through which the blood 
is poured into the auricle or top chamber of the left side of the 
heart. From here, it is pumped down into the ventricle or bottom 
chamber, and with a mighty throb, the heart drives it all over 
the body. It rushes out, dividing and sub-dividing into smaller 
and smaller channels, until they are so small that a strong micro- 
scope is needed to see them. Through the walls of these tiny 
blood vessels nourishment is supplied to the cells of the body, 
and the dead used-up material absorbed ; so that, as.it slowly 
makes its way along, it gives off all the nourishment it is capable 
of for the time being, and with its load of poison, it hurries away 
back to the heart, to be pumped once again into the lungs, to 
be re-vitalized, cleansed, and purified by the oxygen in the air 
we breathe. 
How WE POISON ouR BLOoop. 
There are more ways of poisoning our blood than breathing 
impure air. A good many of the liquids and foods which we 
swallow also poison the blood. People make themselves ill by 
eating wrong foods, or too much food, and instead of fasting 
they swallow great quantities of poisonous drugs. Drugs should 
not be taken, unless by a physician’s orders. 
If the foods which we eat are not thoroughly digested they 
ferment and become putrid, especially animal food, in the 
bowels. The liquid portion of this putrid mass is sucked up by 
little vessels known as lacteals, and poured into the blood, fouling 
and poisoning it. The phagosytes or white blood corpuscles are 
