o me."

That pleased Billy. It made him feel prouder than ever. And the
next morning he was up bright and early. Sometimes he was very slow
about dressing, because he stopped to play. And that made him late
to breakfast. But this morning he was even ahead of time.

As soon as Mrs. Woodchuck had finished her meal of plantain leaves,
Billy reminded her that she had promised to look at his play-house.

She followed him through the front door that he had made, walked to
the end of the tunnel, and into the tiny chamber.

Once inside that room Mrs. Woodchuck took one quick look all
around. And then she turned and ran out as fast as her short legs
would carry her, calling all the time to Billy to hurry. When she
reached the open air Mrs. Woodchuck had to sit down and fan
herself, she was so excited.

"Why did you come out so soon--and so fast?" Billy asked her.

"That's nothing but a trap," his mother said. "You haven't built
any back door. And if a weasel or a mink or a snake should come in
after you, there you'd be, with no way to escape.... I haven't had
such a fright for years."

Billy Woodchuck looked foolish. He had never once thought about a
back door. But after that he never forgot to build one. He saw that
a back door was something that every house ought to have.

XVII

BILLY BRINGS THE DOCTOR

Billy Woodchuck was alarmed. His mother had come home very ill. At
least, that was what Billy thought. It was a warm summer's day; but
Mrs. Woodchuck seemed to be freezing with cold. Her teeth chattered
so hard that the sound filled the whole house. And when Billy asked
her what was the matter with her she did not say a word.

Then he was sure she was ill. For she was a great talker. This was
the first time he had ever seen her when she could not speak.

Now, Mr. Woodchuck was not at home. And none of the children knew
what to do. So Billy left the house and hurried over to find Aunt
Polly Woodchuck--an old lady who was a famous herb doctor.
Woodchucks for miles around came to see her when they were not
feeling well. And she would give them a peppermint leaf to chew, or
some tansy, or maybe a drink of catnip tea. And everybody said that
her medicines never did anyone a bit of harm.

Luckily, Billy found Aunt Polly at home. And he quickly told her
about his mother.

"You say her teeth chatter?" the old lady asked.

"Yes, Aunt Polly!"

"Do they make a clattering noise?"

"Yes, Aunt Polly!"

Aunt P