Personality of plants

SCIENCE IN THE PLANT WORLD
this fact in the cultivation of certain varieties of
Hortensia.
The chemical activities of plants are of in-
calculable value to man. They change air,
water and mineral salts into forms easily assim-
ilable by the human system. Eliminate all the
vegetable life from this planet, and the animals,
including man, would perish in a few months.
Man has also learned to make abundant use of
plant substances for innumerable purposes.
Potash is an example of how the plants come
to our aid in furnishing us a valuable chemical.
It is extracted from wood, Seaweed and
Banana stalks. These plants have discovered
a way of getting it out of its well-nigh insoluble
earth combinations with silica. If it had not
been for certain industrious sea plants, man
would probably never have been aware of the
important chemical twins, bromine and iodine,
so important in photography. These plants
patiently filter them out of sea water where they
exist in microscopic quantities, and build them
into their bodies. Beer is possible because
germinating grains transform amylum or plant
starch into sugar. We find ripe fruits palatable
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