"He must have traveled all night to get here he is such a slow-poke," said Peter Rabbit to his cousin, Jumper the Hare.

Peter wasn't far from the truth. But however he got there, there he was, reaching for lily pads from an old log which lay half in the water, and appearing very well satisfied with life. You know there is nothing like a good meal of things you like, to make everything seem just as it should.

Old Mother Nature seated herself on one end of Paddy's dam and called the school to order. Just as she did so a brown head popped out of the water close by and a pair of anxious eyes looked up at Old Mother Nature.

"It is quite all right, Paddy," said she softly. "These little folks are trying to gain a little knowledge of themselves and other folks, and we are going to have this morning's lesson right here because it is to be about you."

Paddy the Beaver no longer looked anxious. There was a sparkle in his eyes. "May I stay?" he asked eagerly. "If there is a chance to learn anything I don't want to miss it."

Before Old Mother Nature could reply Peter Rabbit spoke up. "But the lesson is to be about you and your family. Do you expect to learn anything about yourself?" he demanded, and chuckled as if he thought that a great joke.

"It seems to me that some one named Peter learned a great deal about his own family when he first came to school to me," said Old Mother Nature. Peter had grace enough to hang his head and look ashamed. "Of course you may stay, Paddy. In fact, I want you to. There are some things I shall want you to explain. That is why we are holding school over here this morning. Just come up here on your dam where we can all get a good look at you."

Paddy the Beaver climbed out on his dam. It was the first time Happy Jack Squirrel ever had seen him out of water, and Happy Jack gave a little gasp of surprise. "I had no idea he is so big!" he exclaimed.

"He is the biggest of all the Rodents in this country, and one of the biggest in all the Great World. Also he is the smartest member of the whole order," said Old Mother Nature.

"He doesn't look it," said Chatterer the Squirrel with a saucy jerk of his tail.

"Which means, I suppose, that you haven't the least doubt that you are quite as smart as he," said Old Mother Nature quietly, and Chatterer looked both guilty and a little bit ashamed. "I'll admit that you are smart, Chatterer, but often it is in a wrong way. Paddy is smart in the very best way. He is a lumberman, builder and engineer. A lot of my little people are workers, but they are destructive workers. The busier they are, the more they destroy. Paddy the Beaver is a constructive worker. That means that he is a builder instead of a destroyer."

"How about all those trees he cuts down? If that isn't destroying, I don't know what is!" said Chatterer, and with each word jerked his tail as if somehow his tongue and tail were connected.

"So it is," replied Old Mother Nature good-naturedly. "But just think of the number of trees you destroy."

"I never have destroyed a tree in my life!" declared Chatterer indignantly.

"Yes, you have," retorted Old Mother Nature.

"I never have!" contradicted Chatterer, quite forgetting to whom he was speaking.

But Old Mother Nature overlooked this. "I don't suppose you ever ate a chestnut or a fat hickory nut or a sweet beechnut," said she softly.

"Of course," retorted Chatterer sharply. "I've eaten ever and ever and ever so many of them. What of it?"

"In the heart of each one was a little tree," explained Old Mother Nature. "But for you very many of those little trees would have sprung up and some day would have made big trees. So you see for every tree Paddy has destroyed you probably have destroyed a hundred. You eat the nuts that you may live. Paddy cuts down the trees that he may live, for the bark of those trees is his food. Like Prickly Porky he lives chiefly on bark. But, unlike Prickly Porky, he doesn't destroy a tree for the bark alone. He wastes nothing. He makes use of every bit of that tree. He does something for the Green Forest in return for the trees he takes."

Chatterer looked at Happy Jack and blinked in a puzzled way. Happy Jack looked at Peter Rabbit and blinked. Peter looked at Jumper the Hare and blinked. Jumper looked at Prickly Porky and blinked. Then all looked at Paddy the Beaver and finally at Old Mother Nature, and all blinked. Old Mother Nature chuckled.

"Don't you think the Green Forest is more beautiful because of this little pond?" she asked. Everybody nodded. "Of course," she continued. "But there wouldn't be any little pond here were it not for Paddy and the trees he has cut. He destroyed the trees in order to make the pond. That is what I meant when I called him a constructive worker. Now I want you all to take a good look at Paddy. Then he will show us just how as a lumberman he cuts trees, as a builder he constructs houses and dams, and as an engineer he digs canals."

As Paddy sat there on his dam, he looked rather like a giant member of the Rat family, though his head was more like that of a Squirrel than a Rat. His body was very thick and heavy, and in color he was dark brown, lighter underneath than above. Squatting there on the dam his back was rounded. All together, he was a very clumsy-looking fellow.

Peter Rabbit appeared to be interested in just one thing, Paddy's tail. He couldn't keep his eyes off it.

Old Mother Nature noticed this. "Well, Peter," said she, "what have you on your mind now?"

"That tail," replied Peter. "That's the queerest tail I've ever seen. I should think it would be heavy and dreadfully in the way."

Old Mother Nature laughed. "If you ask him Paddy will tell you that that tail is the handiest tail in the Green Forest," said she. "There isn't another like it in all the Great World, and if you'll be patient you will see just how handy it is."

It was  a queer-looking tail. It was broad and thick and flat, oval in shape, and covered with scales instead of hair. Just then Jumper the Hare made a discovery. "Why!" he exclaimed, "Paddy has feet like Honker the Goose!"

"Only my hind feet," said Paddy. "They have webs between the toes just as Honker's have. That is for swimming. But there are no webs between my fingers." He held up a hand for all to see. Sure enough, the fingers were free.

"Now that everybody has had a good look at you, Paddy," said Old Mother Nature, "suppose you swim over to where you have been cutting trees. We will join you there, and then you can show us just how you work."

Paddy slipped into the water, where for a second or two he floated with just his head above the surface. Then he quickly raised his broad, heavy tail and brought it down on the water with a slap that sounded like the crack of a terrible gun. It was so loud and unexpected that every one save Old Mother Nature and Prickly Porky jumped with fright. Peter Rabbit happened to be right on the edge of the dam and, because he jumped before he had time to think, he jumped right into the water with a splash. Now Peter doesn't like the water, as you know, and he scrambled out just as fast as ever he could. How the others did laugh at him.

"What did he do that for?" demanded Peter indignantly. "To show you one use he has for that handy tail," replied Old Mother Nature. "That is the way he gives warning to his friends whenever he discovers danger. Did you notice how he used his tail to aid him in swimming? He turns it almost on edge and uses it as a rudder. Those big, webbed hind feet are the paddles which drive him through the water. He can stay under water a long time—as much as five minutes. See, he has just come up now."

Sure enough, Paddy's head had just appeared clear across the pond almost to the opposite shore, and he was now swimming on the surface. Old Mother Nature at once led the way around the pond to a small grove of poplar trees which stood a little way back from the water. Paddy was already there. "Now," said Old Mother Nature, "show us what kind of a lumberman you are."

Paddy picked out a small tree, sat up much as Happy Jack Squirrel does, but with his big flat tail on the ground to brace him, seized the trunk of the tree in both hands, and went to work with his great orange-colored cutting teeth. He bit out a big chip. Then another and another. Gradually he worked around the tree. After a while the tree began to sway and crack. Paddy bit out two or three more chips, then suddenly slapped the ground with his tail as a warning and scampered back to a safe distance. He was taking no chances of being caught under that falling tree.

The tree fell, and at once Paddy returned to work. The smaller branches he cut off with a single bite at the base of each. The larger ones required a number of bites. Then he set to work to cut the trunk up in short logs. At this point Old Mother Nature interrupted.

"Now show us," said she, "what you do with the logs."

Paddy at once got behind a log, and by pushing, rolled it ahead of him until at last it fell with a splash in the water of a ditch or canal which led from near that grove of trees to the pond. Paddy followed into the water and began to push it ahead of him towards the pond.

"That will do," spoke up Old Mother Nature. "Come out and show us how you take the branches."

Obediently Paddy climbed out and returned to the fallen tree. There he picked up one of the long branches in his mouth, grasping it near the butt, twisted it over his shoulder and started to drag it to the canal. When he reached the latter he entered the water and began swimming, still dragging the branch in the same way. Once more Old Mother Nature stopped him. "You've shown us how you cut trees and move them, so now I want you to answer a few questions," said she.

Paddy climbed out and squatted on the bank.

"How did this canal happen to be here handy?" asked Old Mother Nature.

"Why, I dug it, of course," replied Paddy looking surprised. "You see, I'm rather slow and clumsy on land, and don't like to be far from water. Those trees are pretty well back from the pond, so I dug this canal, which brings the water almost to them. It makes it safer for me in case Old Man Coyote or Buster Bear or Yowler the Bobcat happens to be looking for a Beaver dinner. Also it makes it very much easier to get my logs and branches to the pond."

Old Mother Nature nodded. "Just so," said she. "I want the rest of you to notice how well this canal has been dug. At the other end it is carried along the bottom of the pond where the water is shallow so as to give greater depth. Now you will understand why I called Paddy an engineer. What do you do with your logs and branches, Paddy?"

"Put them in my food-pile, out there where the water is deep near my house," replied Paddy promptly. "The bark I eat, and the bare sticks I use to keep my house and dam in repair. In the late fall I cut enough trees to keep me in food all winter. When my pond is covered with ice I have nothing to worry about; my food supply is below the ice. When I am hungry I swim out under the ice, get a stick, take it back into my house and eat the bark. Then I take the bare stick outside to use when needed on my dam or house."

"How did you come to make this fine pond? " asked Old Mother Nature.

"Oh, I just happened to come exploring up the Laughing Brook and found there was plenty of food here and a good place for a pond," replied Paddy. "I thought I would like to live here. Down where my dam is, the Laughing Brook was shallow—just the place for a dam."

"Tell us why you wanted a pond and how you built that dam," commanded Old Mother Nature.

"Why, I had to have a pond, if I was to stay here," replied Paddy, as if every one must understand that. "The Laughing Brook wasn't deep or big enough for me to live here safely. If it had been, I would have made my home in the bank and not bothered with a house or dam. But it wasn't, so I had to make a pond. It required a lot of hard work, but it is worth all it cost.

"First, I cut a lot of brush and young trees and placed them in the Laughing Brook in that shallow place, with the butts pointing up-stream. I kept them in place by piling mud and stones on them. Then I kept piling on more sticks and brush and mud. The water brought down leaves and floating stuff, and this caught in the dam and helped fill it in. I dug a lot of mud in front of it and used this to fill in the spaces between the sticks. This made the water deeper in front of the dam and at the same time kept it from getting through. As the water backed up, of course it made a pond. I kept making my dam longer and higher, and the longer and higher it became the bigger the pond grew. When it was big enough and deep enough to suit me, I stopped work on the dam and built my house out there."

Everybody turned to look at Paddy's house, the roof of which stood high out of water a little way from the dam. "Tell us how you built that," said Old Mother Nature quietly.

"Oh, I just made a big platform of sticks and mud out there where it was deep enough for me to be sure that the water could not freeze clear to the bottom, even in the coldest weather," replied Paddy, in a matter-of-fact tone. "I built it up until it was above water. Then I built the walls and roof of sticks and mud, just as you see them there. Inside I have a fine big room with a comfortable bed of shredded wood. I have two openings in the floor with a long passage leading from each down through the foundations and opening at the bottom of the pond. Of course, these are filled with water. Some houses have only one passage, but I like two. These are the only entrances to my house.

"Every fall I repair my walls and roof, adding sticks and mud and turf, so that now they are very thick. Late in the fall I sometimes plaster the outside with mud. This freezes hard, and no enemy who may reach my house on the ice can tear it open. I guess that's all."

Peter Rabbit drew a long breath. "What a dreadful lot of work," said he. "Do you work all the time?"

Paddy chuckled. "No, Peter," said he. "In the spring and summer I like to play and go on exploring trips. But when it is time to work, I work every minute. I believe in working with all my might when it is time to work, and playing the same way in play-time."

Old Mother Nature nodded in approval. "Quite right," said she. "Quite right. Are there any more questions?"

"Do you eat nothing but bark?" It was Happy Jack Squirrel who spoke.

"Oh, no," replied Paddy. "In summer I eat berries, mushrooms, grass and the leaves and stems of a number of plants. In winter I vary my fare with lily roots and the roots of alder and willow. But bark is my principal food."

Old Mother Nature waited a few minutes, but as there were no more questions she added a few words. "Now I hope you understand why I am so proud of Paddy the Beaver, and why I told you that he is a lumberman, builder and engineer," said she. "For the next lesson we will take up the Rat family."