"But how could we mark it?" said Rollo.
"Why, we could drive a little stake unto the ground."
"O, that would not do," said Rollo. "People would trip over them, and break them down. They would be exactly in the walk."
Lucy saw that this would be a difficulty, and, for a moment, seemed to be at a loss. At length, she said,
"We might go somewhere else, then, where the people would not come."
"But what should we do for a post?" said Rollo.
"Could not we get Jonas to drive a tall stake down?" said Lucy.
"Yes," said Rollo; "I suppose so."
The children went out into the garden to find a good smooth place, and while they were walking about there, Rollo's mother came out, and they told her the whole story. She seemed quite interested in the plan, and told them of a better way than any that they had thought of.
"You see," said she, "that the height of the stake or pole that makes the shadow is not material; for the shadow of a small one will vary just as much, in proportion to its length, as that of a long one will. So, instead of taking a wooden stake, out of doors, you might take a large pin, and drive it down a little way into the window sill, in the house. Then you can mark the shadow with a pen, very exactly."
"So we can," said Lucy, clapping her hands.
"And you might put a piece of white paper, or a card down first," continued Rollo's mother, "and drive the pin through that, and then mark the places where the end of the shadow comes every day, directly on the card, with a fine pen. Thus you could be a great deal more exact than you can in chalking upon a barn floor."
Rollo asked his mother if she would not be kind enough to help them fix their apparatus; but she said she would give them particular directions, though she should prefer letting them do the whole themselves, and then, if they met with any difficulties, they might come and report them to her, and she would tell them how to surmount them. So she recommended to them to go and find a blank card, or piece of white pasteboard, or of stiff white paper, as big as a common card. "Then," said she, "choose some window where the sun shines in at noon, and put the card down upon the sill, and drive the pin down through it. But you must not drive the pin through the middle of the card, for the shadow will always be off to the north of the pin, and therefore the pin may be pretty near the south end of the card. Then the shadow will be more likely to come wholly upon the card, even when it is longest. You had better place the card in such a position, too, that its sides shall lie in the direction of north and south. Then the shadow at noon will lie along exactly in the middle of it. You must get a large and stout pin, too; and drive it in firmly, a little way, with a small hammer. It will be well, too, to drive another smaller pin into the other end of the card, so as to keep it fixed in its north and south position."
"How can we know when it is north and south, exactly?" said Lucy.
"You cannot do it exactly," said Rollo's mother; "but you can get it pretty near. One way is to borrow father's little compass, and adjust it by that. Another way is to see when it is exactly twelve o'clock by the clock, and then the shadow of the pin will of itself be about north.
"Then you might move the north end of the card until the shadow is brought exactly into the middle of the card, and then put the other pin in, and fix it in that place. Then if you make a mark along where the shadow comes, that mark will be a north and south line, and you can mark the place where the shadow of the pin's head crosses that line, when it crosses it every day at noon."
The children said that they believed they understood the directions, and they determined to try the plan. They thought they would fix two cards, one at Rollo's house, and one at Lucy's; and they immediately went off in pursuit of blank cards and big pins.
PRUNING.
One afternoon, Rollo saw his father coming out into the garden, with a little saw and a knife, and a small pot of paint in his hands.
"Father," said he, "are you going to prune your trees now?"
"Yes," said his father.
"Then, shall I go and get my wheelbarrow?"
"Yes," replied his father, again.
So Rollo ran off after his wheelbarrow. It had been arranged, between him and his father that morning, that they should work in the garden an hour or two in the afternoon, and that Rollo should pick up all the cuttings from the trees, and wheel them away, and then, when they were dry, make a bonfire with them.
Rollo found his wheelbarrow in its proper place, and trundled it along into the garden.
"Father," said he, "what trees are you going to prune first?"
"O, I am going to begin at the back side of the garden, and prune them all, advancing regularly to the front."
"What is the saw for?" said Rollo.
"To saw off the large branches, that I can't cut off easily with a knife."
"But I should not think you would want to saw off any large branches, for so you will lose all the apples that would grow on them next year."
"Why, sometimes, the branches are dead, and then they would do no good, but only be in the way."
"But do they do any hurt?" said Rollo.
"Why, they look badly."
"But, I mean, would they do any actual hurt to the tree?"
"Why, I don't know," said his father; "perhaps they would not. At any rate, if I cut them off pretty close to the living part of the tree, the bark will then gradually extend out over the little stump that I leave, and finally cover it over, and take it all in, as it were."
By this time, Rollo and his father had reached the back side of the garden, and his father showed him the place where he had cut off a limb the year before, and he saw how the fresh young bark had protruded itself all around it, and was spreading in towards the centre so as to cover it over. Rollo then saw that it was better that all old dead limbs should be cut off.
"That's curious," said Rollo.
"Yes, very curious," said his father. "A tree will take in, and cover up, almost any thing that is fastened to the wood, in the same manner."
"Will it?" said Rollo.
"Yes," said his father. "If you drive a nail into a tree, the bark will, after a time, cover it over entirely. Sometimes people find things in old trees, which were put upon them when they were young."
"How big things?" said Rollo.
"O, I don't know exactly how big. The tree will make an effort to enclose any thing small or large. Only, if it is very large, it will take a great while to enclose it, and it might be so large that it never could enclose it."
"Well, father, how large must it be so that the tree never could enclose it?"
"O, I don't know, exactly. Once I saw a tree that was growing very near a rock. After a time it came in contact with it, and it grew and pressed against it, until the rock crowded into the wood. Then the bark began to protrude in every direction along the rock, as if it was making an effort to spread out and take the rock all in. But I don't think it will ever succeed; for the rock was part of a ledge in a pretty large hill."
"What a silly tree!" said Rollo.
"Father, I believe I will try the experiment some time," continued Rollo, after a pause.
"Very well," said his father.
"What shall I put into the tree?" asked Rollo.
"You might put in a cent," said his father, "and then, if it should get fairly enclosed, I presume the tree will keep it safe for you a good many years."
Rollo determined to do it. "Then," said he, "I shall never be out of money, and that will be excellent." His father told him that he must make a small cleft in the bark and wood, with a chisel and mallet, and then drive the cent in, edgewise, a little way.
So Rollo got his chisel and mallet, and inserted the cent according to his father's directions, and by that time there were a good many branches and twigs on the ground, which his father had taken off from the trees, and so he began to pick them up, and put them into his wheelbarrow.