e of the party should be eaten
first."

"Ugh! don't joke like that, Dave," begged Mina. "Maybe we _will_ be
dreadfully hungry before we get out of this place."

"I'm hungry now," announced Frankie.

"It _is_ near time for luncheon," agreed Wyn.

"'Luncheon'! Huh!" ejaculated Dave. "I s'pose that's the feminine of
'lunch.' I could eat a stack of pancakes and a whole can of beans right
now. I'm too hungry for any mere 'luncheon.'"

"Oh, dear! It's so hot down here," sighed Percy. "If we've got to stay,
let's go upstairs again, where there is some air stirring."

"Let's wave a signal from the window. Maybe somebody will see it and
come to our rescue," suggested Frank.

"And what could they do?" demanded Wyn, "These sails can't be stopped
from the outside; can they, Dave?"

"Not that I know of," replied Dave. "If there was a tree near, a fellow
might tie a kedge rope to it, and then throw the kedge over one of the
arms. But that would tear the machinery all to pieces, I suppose, it
would stop it with such a jerk."

Just then Mina Everett uttered a shrill cry of alarm. "Look! Look!" she
cried. "It's afire! We'll burn up in here! Oh, oh, Wynnie! what shall we
do?"

The others turned, aghast There _was_ blue smoke spurting out
around the shaft above their heads.

CHAPTER XXII

THE PRISONERS OF THE TOWER

"Fire!" cried Percy Havel. "Oh! what _shall_ we do?"

"Well, your yelling about it won't put it out," snapped Frank.

But Dave Shepard had sprung up the ladder and immediately announced the
trouble.

"The axle is getting overheated. See that can of oil yonder, Ferd? Come
out of your trance and do something useful, boy! Quick! hand me the
can."

But it was Wyn who got it to him. Dave quickly refilled the oil cups and
squirted some of the lubricant into the cracks about the shaft. The
smoke immediately drifted away.

"The rest of you go up where it's cooler," he commanded. "I will remain
here and play engineer. And for goodness' sake, pray for the wind to die
down!"

The situation was really serious; nobody among the prisoners of the
tower knew what to do.

While the wind swung the arms of the mill round and round, there was no
chance to get out. Not that they did not all cudgel their brains within
the next hour to that end. There were enough suggestions made to lead to
a dozen escapes; only--none of the suggestions were practical.

It was less noisy, now that Dave had stopped the millstones;