Vitamin Bi 173
earliest inventions in the evolution of life. It is probably
present and necessary in all living things, although the quan-
tity, except where it is especially stored, is usually less than
one part in a million. It is necessary for bacteria, fungi,
green plants, and all kinds of animals, from amoebae to
whales.
Without thiamin, respiration in living organisms is inter-
fered with ; the burning of carbohydrates to provide energy
cannot go on in a normal manner. The rich deposit of
thiamin in the germ of starchy seeds is clearly a provision on
the part of Nature to enable the germinating plant to use
the starch for energy with which to grow until it can spread
its leaves to the sun, whereupon it is able to manufacture
more thiamin for its continued use. As Dr. Williams has
said, man commits a crime against Nature when he eats the
starch from the seed and throws away the mechanism neces-
sary for its utilization. The starch without thiamin is like a
safety match without the scratching surface.
Green plants, and many fungi, yeasts, and bacteria are
able to manufacture thiamin, but no higher animals are cap-
able of doing so. Green plants make it only in the upper
parts, not in their roots, so no root growth is possible with-
out a supply of thiamin either from a supply stored in a seed
or from the green portion of a plant. A recent study showed
that when root-tips are removed from their parent plants
they fail to grow in a plain solution of sugar and mineral
salts, but grow well if there is added one part of thiamin in
500,000,000,000 parts of the culture medium. Soaking
roots of transplanted plants in a dilute thiamin solution
keeps them from wilting, and watering them with it stimu-
lates growth.
In cuttings, the green parts supply enough thiamin to
start meager root growth, but much more rapid growth is