"The tree"s coat," said Norah. "What do you mean?" "Come into the garden," said Will, "and we"ll show you. Look at this old tree. How rough and gnarled its stem and branches look. This outside part of the tree is quite different from the rest of the woody stem.
We call it the bark. This is what I meant by the tree"s coat.""Will is quite right," said Fred, "only I should perhaps call it, as teacher did, a double coat, for there is an inner one beneath this rough one on the outside.
"But let us look at some of the other plants in the garden," Fred continued. "I can easily peel off from any of them an outer skin or covering. It is not so thick, of course, as the tree"s coat, but it is the same sort of thing. It covers the plants just as the skin covers our bodies. It is in each case the bark of the plant.
"The outer bark which we can see is, of course, thicker and coarser than the one beneath it. We might call this the tree"s greatcoat. The cork which we use for so many purposes is the outer bark of a kind of oak tree which grows in Spain. These trees are grown only for their bark, which is stripped off them from time to time.
