The fact that the branches were not covered with snow certainly looked as if they had been put there rather recently in a crude effort to hide the entrance to something—perhaps a cave.

“That’s worth having a look at,” he said, jerking the sled up to him and tightening his hold on Billie’s arm. “Can you make it, Billie? The snow seems to be deeper over this way.”

“Oh, I can make it all right,” answered Billie, stoutly, as she clenched her teeth and shut her eyes and floundered on through the clinging snow. “I guess I’ve got to make it!” she added, to herself.

They had almost reached their goal when suddenly they stepped into a hole hidden by the snow and sank down in the icy whiteness until Billie was almost up to her neck.

“Gosh,” cried Teddy, as he struggled out to higher ground, pulling his thoroughly frightened companion after him, “I hope there aren’t many more places like that around here. We’ll make it all right, Billie. Say! you’re not crying, are you?” he broke off, with a boy’s utter terror of tears, as Billie dug two mittened and numbed hands into her smarting eyes.

“No, I’m not crying,” she answered, giving him a rather watery smile. “I’m laughing. Can’t you see I am?”

“Poor little kid,” said Teddy for the second time that afternoon, and the sympathy in his voice pretty nearly did send Billie into a downpour of tears. She was so thoroughly miserable that it was all she could do to keep from wailing her grief aloud. But Teddy had put one big protecting arm around her now and was half carrying her over to that strange object that looked so dark against the gleaming bank of snow.

Then he let Billie go, and while she shivered by herself he laid hold of the branches and pulled with all his might.

“Ooh, look out!” called Billie. “There might be a bomb or something at the other end. Oh-h!” The queer doorway gave so easily before the boy’s strength that he was sent staggering back against the snowdrift and sat down in it most uncomfortably.

The next minute he was up again, had swept the branches and twigs aside, and was examining the exposed opening with all a boy’s eager curiosity. Billie peered eagerly over his shoulder.