In one terrible instant the girls realized what might happen when what was discomfort to the animals now, should become torture. Maddened by pain and fright, it would be no longer possible to quiet them. And then—and then——
"Don't you think we'd better stop and try to quiet the horses?" asked Mollie once, as the champing and snorting in the blackness behind them became more marked.
"I don't think it would do any good," Betty answered between clenched teeth as she scooped and dug, scooped and dug. "Better keep on working, girls. It's the one chance we have."
Oh, the horror of it, the nightmare of it! The heavy air, the hideous dark, the nervous trampling of those death-bearing hoofs—— The girls spoke no longer. They were beyond speech. Almost maddened by terror themselves, they scooped and dug, scooped and dug——
Once they thought they heard voices outside, and shrilly they cried to their imaginary rescuers. No answering "hallo" reached them, and the only effect of their cries seemed to be to add to the fright of their horses and so endanger themselves still more.
On, on, on—while their aching muscles seemed to grow numb with the strain and their lungs nearly burst with the pressure upon them.
At last they gave in—it seemed that they had to give in. All except Betty, who kept on desperately, doggedly, her muscles barely able to respond to the last call she was making upon them.
"I can't go on any more. I'm all in," said Mollie, a desperate quiet in her voice. "My arms are like lead and my hands are so numb I can't feel the stone. I guess this is the last adventure of the Outdoor Girls. We have just had one too many, that's all."
"Oh, Mollie!" Betty drew in a labored breath that caught on a sob. "Please don't give up—please! I've counted on you——" she paused, jerked her head up, her attention turned on the spot where her hand still automatically dug at the earth.
She sniffed, experimentally, sniffed again, stilling the wild throb of hope that was almost a pain at her heart.