won't it?"

Then her uncle told her how the coming in of the tide changes just as
the rising of the moon does, and that one must know the difference in
time to be sure. Then he went on to explain something about the small
creatures which inhabited the pools, the barnacles which covered the
rocks up to a certain point.

"Why don't the barnacles go any higher?" asked Polly. "I should think
they would grow and grow just like grass does over bare places in the
ground.

"They extend only to high water-mark," her uncle told her, "for you see
they are fed by the ocean. If you will watch closely, you can see them
open and close as the waves come and go."

"Isn't it wonderful?" said Polly in an awe-struck voice.

"I like it best when the tide is up," remarked Molly, "for I don't
think all that dark sea-weed that covers the rocks is very pretty."

Polly looked down at the long ropes of seaweed which clung to the
craggy places beneath them. "It makes the rocks look just like
buffaloes or some strange kind of animals," she said. "I shall call
that Buffalo Rock, and that other the Lion's Den, for it looks like a
lion lying down."

"There is a dear place further down," said Molly. "It is sheltered
from the wind and we have tea there sometimes. There is a cunning
fireplace that Uncle Dick built there last year. I wonder if it is
still standing. Let's go and see."

They followed the shore a little further and found a flat rock not far
below the top of the bluff. The fireplace was nearly as they had left
it, and only required a few stones to make it as good as new. Molly
viewed it with a satisfied air as her uncle topped it with a final
stone. "There," she exclaimed, "it is ready for our first afternoon
tea! We'll toast marshmallows, too, as soon as we can get some at the
store."

"Why can't we get them to-day?" asked Polly who did not want to put off
such a pleasure.

"Because Mr. Hobbs never has any before the Fourth of July. He always
gets in his good things then, but never a day sooner or later. I know
him of old," said Dick.

"By that time Mary will be here," said Molly thoughtfully, "and we can
have our first tea-party in her honor."

"Yes, and she can help us make our Fourth," said Uncle Dick, laughing.
"She has never known our great and glorious Fourth over there in
England."

"Of course not," said Polly. "I forgot she was a wicked Britisher."

"Not very wicked," said Uncle Dick.

"But we m