d made her
nervous, and for the first time in a long while she felt afraid.

"Oh, I wish John would hurry and catch up with us!" she exclaimed.
"Please don't fall, Scylla--hang on to the pommel tight."

Scylla, who had stopped crying, told Martha not to worry, that she would
not fall; and the slow journey over the prairie continued silently for a
minute or two. Every once in a while Martha turned back and looked
toward the flickering camp-fire of the cow-boys. An exclamation of
surprise was drawn from her when she failed to see it shining in the
distance, and she stopped. Then, faintly, she heard shouts and the
thumping of racing hoofs on the prairie.

"John is coming at last," she said.

But then she realized that more than one animal's hoofs were drumming
desperately on the turf. While she stood wondering if some of the
cow-boys were coming home with John, she heard the hoof-beats merge into
a steady roar. Even the shouts of the men which she had just heard were
drowned in this dull, threatening rumble. For just an instant she
thought it was thunder, and then her quick reasoning told her the truth.

The herd had stampeded!

That she and Scylla were directly in its path she was certain, for the
camp-fire had, a moment before, been between them and the herd and
was now invisible. It had either been trampled out or was hidden by the
advancing mass of cattle.

[Illustration: "JUST THEN ANOTHER FLASH CAME AND SHOWED A COW-BOY
LEANING FAR OVER THE NECK OF HIS PONY, RIDING FOR HIS LIFE."]

Martha well knew what it meant to be in the path of a stampede; but,
strangely enough, all her fear left her. She was puzzled, that was all.
Had she been alone, she could easily have escaped by jumping on Dan's
back and riding hard. Dan could have distanced the cattle, even when
they were stampeding. But now she had helpless Scylla to take care of.

The advancing thunder-clouds had wholly hidden the moon and put the
prairie in inky darkness. At first Martha thought of starting Dan away
with Scylla and trusting to Providence to keep the little invalid on his
back, while she remained to face the danger alone; then she thought of
trying to ride with her. But she knew Scylla could not possibly keep her
place in the saddle of the horse while he ran, even if she herself
should mount him too and try to hold Scylla on.

She stepped back to Scylla's side. There was a deathly doubt in her
heart as to whether she was doing the right thing;