Peter was much puzzled, for, do what he could， he was unable to find out what the frolicking creature did with herself during the day. At length he made up his mind not to take his eyes off her during the whole day. He watched her closely and saw that, when the flock passed the corner of an old broken-down wall at the foot of a hill, she quietly dropped behind and was out of sight in a moment.
Peter ex***ned the wall. He had seen it many a time before. People said that it was part of the ruins of an old castle. As he looked closely he saw that, just behind a hawthorn bush, there was a hole large enough for a goat, or even a man on all-fours, to pass through. This, then, was the place where Nanny disappeared so strangely; indeed, she had worn quite a path beneath the hawthorn, and the only wonder was that her master had not discovered it before.
The next day Peter watched her as before, and when she ran slyly through the wall he followed her. After creeping on his hands and knees for some distance he found himself in a long and lofty cavern. The sunlight streamed through some crevices in the rocks and made the place look quite light and cheerful. At the farther end he saw Nanny busily picking up some oats that were scattered on the floor. How did the oats come there? The plump grains were constantly trickling down from above, and the goat had nothing to do but stand and eat.
Peter could not understand it. But as he came nearer he heard the stamping of heavy feet overhead and the whinnying of horses.
“Oh, somebody has a stable up there,” he said to himself，“but how can that be? I have been all over these hills, and have never seen even the sign of a house.”
As he was looking about him, a door in the side of the cavern suddenly opened and a queer little fellow with a big head and saucer eyes came in.
“Good morning to you, sir,” said Peter, thinking it was the stable man.“I beg you will pardon me for coming in without any invitation. Is there anything I can do to serve you?”
The little man made no answer, but looked at Peter funnily with those great eyes, and beckoned him to follow.
Peter was too good-natured to refuse, and besides this he was curious to learn all about the strange place. So he followed his queer guide through the door and up a long flight of stairs until he again felt the warm sun