siegers. They
kept up a desultory firing all afternoon. Now and then a reckless grader
running from post to post drew a volley from the Sioux; and likewise
something that looked like an Indian would call forth shots from the
defenses. But there was no real fighting.

It developed that the Sioux were waiting for night. A fiery arrow,
speeding from a bow in the twilight, left a curve of sparks in the air,
like a falling rocket. It appeared to be a signal for demoniacal yells
on all sides. Rifle-shots ceased to come from the slopes. As darkness
fell gleams of little fires shot up from all around. The Sioux were
preparing to shoot volleys of burning arrows down into the camp.

Anderson hurried in to consult with Baxter. "We're surrounded," he
said, tersely. "The redskins are goin' to try burnin' us out. We're in a
mighty tight place."

"What's to be done?" asked Baxter.

Anderson shook his head.

On the instant there was a dull spat of an object striking the roof over
their heads. This sound was followed by a long, shrill yell.

"That was a burnin' arrow," declared Anderson.

The men, as of one accord, ran out through the engineers' quarters to
the open. It was now dark. Little fires dotted the hillsides. A dull red
speck, like an ember, showed over the roof, darkened, and disappeared.
Then a streak of fire shot out from the black slope and sped on clear
over the camp.

"Sooner or later they'll make a go of that," muttered Anderson.

Neale heard the scout's horse, that had been left there in the
inclosure.

"Anderson, suppose I jump your horse. It's dark as pitch. I could run
through--reach the troops. I'll take a chance."

"I had that idee myself," replied Anderson. "But it seems to me if them
troopers wasn't havin' hell they'd been here long ago. I'm lookin' for
them every minnit. They'll come. An' we've got to fight fire now till
they get here."

"But there's no fire yet," said Baxter.

"There will be," replied Anderson. "But mebbe we can put it out as fast
as they start it. Plenty of water here. An' it's dark. What I'm afraid
of is they'll fire the tents out there, an' then it 'll be light as day.
We can't risk climbin' over the roofs."

"Neale, go inside--call the boys out," said Baxter.

Neale had to feel his way through the rooms. He called to his comrades,
and then to the women to keep up their courage--that surely the troops
would soon return.

When he went out again the air appeared full of fi