answered the strange cry with a whinny that startled the echoes of
the cavern like bats about their ears.

"Oh, don't, Do Fuss!" commanded Grace. "Don't be such a bad little
horse. You make it worse."

"He surely would not have neighed if that was a bear shouting at
us," declared Bess.

"Bear, nonsense!" scoffed Rhoda.

"Well, put a better name to it," challenged Bess.

For a third time the eerie cry rang out. The noise completely
silenced Rhoda for the moment. Nan said, with more apparent
confidence than she really felt:

"One thing, it doesn't seem to come nearer. But it gives me the
shakes."

"It can't be that terrible wind blowing into the cavern by some
hole, can it?" queried Bess.

"You are more inventive than practical, Bess," said her chum. "That
is not the wind, I guarantee."

"But what is it, then?"

"I wish I could tell you, girls. But I really cannot guess,"
admitted the girl of Rose Ranch, at last.