50 
THE STORY OR THE OAK TREE 
The cells, then, do all the work of the tree. So that the 
most sensible way to study a tree is not to start with root, 
trunk and branches, but to commence with the cells, 
to examine each cell-mass and find out how its members 
do their work. It is only recently that we have learned 
this best way to study the tree. Formerly, people fol¬ 
lowed the most natural way, they studied first of all those 
parts of the tree that looked biggest and most important, 
the trunk, roots, and branches. It took the man with the 
microscope to set us straight! He showed us that trunk, 
roots and branches grow and take shape solely to serve 
the needs of the tiny cells; he showed us that the well¬ 
being of the cells means the health of the tree, and the 
multiplying of the cells means the growth of the tree. 
He made us turn our eyes from the bulky trunk to the 
twigs and leaves, to the root-ends and the tiny root-hairs. 
These delicate members, he said, are the liveliest parts of 
the tree; do not think of them as separate forms, but 
realize that they are just the trunk and branches length¬ 
ened out in such shapes that they can bring the living 
cells closer to the moisture of the earth, closer to the 
glow of the sunlight. Feeling for moisture is a dainty 
business, the clumsy, hard-skinned trunk could not do 
that; its bark is so thick it could not feel the water, and 
if it could, the water would not soak in. So the trunk 
