the: leap 
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If they are beautiful, as they always are when seen in 
their proper setting, why, so much the better! And 
every part of every plant helps to nourish it or protect 
it, just as every part of you, from your stomach to your 
skin, is either nourishing you or giving you protection. 
You know what the bark does for the tree; it does the 
same thing that your skin does for you, and you know 
what the rest of the trunk does, and what the roots do. 
What part do you suppose the leaves play in the life of 
the tree? 
The leaves are the tree’s many kitchens, where the raw 
food—air and sunlight—is prepared for the tree’s diges¬ 
tion. When you hold an oak leaf in your hand you can 
see in it a line running through the center and little lines 
or veins branching out from the central vein. It is 
through these veins that the root moisture runs into the 
leaf, and then, when it has been mixed with the air- 
food prepared in the leaf kitchen, it runs back again 
through these veins into the twigs and down through the 
trunk. When they first told me that the leaves take in 
air as food for the tree I said, “Yes, but how does the 
leaf do it ? I cannot see any opening in this leaf for the 
air and sunlight to come in!” “No,” they said, “you can¬ 
not see any opening, but the openings are there just the 
same, and the man with the microscope can show them to 
you any day. If he puts an oak leaf under his microscope 
