"Oh, who did it, grandpapa?" said Bessie. "Who painted those leaves? Did Donald?"
"No, darling, no hand of man could paint that. This is the Lord's doing, and it is indeed marvellous in our eyes."
"Do you mean our Father in heaven did it, grandpapa?"
"Yes, dear, it was the great and loving Father, who has not only made his earth to bring forth food and drink for all his creatures, but has also made it so beautiful that it may please and delight our eyes."
"But," said Maggie, in great astonishment, "that vine used to be all green just like the tree. How did it come red?"
"I will tell you," said grandpapa. "Do you know what the sap is?"
"No, sir."
Mr. Duncan looked around him, and then, taking his knife from his pocket, cut a slip from a tall plant which grew near. He pressed it with his thumb and finger, and a small whitish drop oozed slowly out from the end which had been cut.
"See there," he said, "that is the sap or juice of the plant. It is in every tree or bush, and goes running through the trunk, branches, and leaves much as the blood runs through the veins in your body. All through the summer it keeps the branches moist and the leaves fresh and green; but it does not like the cold, and when the frost comes, it runs away from the leaves. Then they begin to turn, some red, some yellow, some brown. Our pretty creepers here are among the first to feel the cold; and they turn sooner than the trees over which they grow. As the weather becomes colder, the sap goes farther and farther away, back through the branches and down through the trunk till it reaches the roots, where it lies snug and close in its winter home under the warm earth. Then the leaves shrivel up and lose their bright colors and fall to the ground. If you break a branch from a tree in winter, it will snap more easily than it will in the summer, because it is dry and brittle from the loss of its sap. All through the cold weather the sap keeps hidden quietly away in the roots; but in the spring when the air grows mild and pleasant, it begins to stir and move upward again. Up, up it goes through the trunk and branches, till, as the weather grows warmer and warmer, the little buds which hold the young leaves and blossoms begin to show themselves, and at last unfold. Then the small tender leaves peep out and gather strength and life from the soft air and bright sunshine and gentle rain, till the trees and bushes are covered with their beautiful green dress and make a pleasant shade for my Maggie and Bessie when they come out to see their old grandpapa at Riverside."