re. This man was in the same
mine with him, until my brother was transferred, and then Mr. Borious
escaped. We will have to change our plans."

"And where are we to head for now?" asked Tom.

"Near to the town of Haskaski, where my poor brother is working in a
sulphur mine!"

"Then let's get a move on!" cried Tom with enthusiasm. "Do you think
this man will come with us, Mr. Petrofsky, to help in the rescue, and
show us the place?"

"He says he will," translated the exile, "though he is much afraid of
our strange craft. Still he knows that to trust himself to it is better
than being captured, and sent back to the mines to starve to death!"

"Good!" cried Tom. "And if he wants to, and all goes well, we'll take
him out of Russia with us. Now get busy, Ned, and we'll have this
machine in shape again soon."

While Ivan Petrofsky took his new friend inside, and explained to him
about the workings of the Falcon, Tom and Ned labored over the gas
machine with such good effect that by night it was capable of being
used. Then they went aloft, and making a change in their route, as
suggested by Mr. Borious, they headed for the desolate sulphur region.

For several days they sailed on, and gradually a plan of rescue was
worked out. According to the information of the newcomer, the best way
to save Mr. Petrofsky's brother was to make the attempt when the
prisoners were marched back from the mines to the barracks where they
were confined.

"It will be dark then," said Mr. Borious, "and if you can hover in your
airship near at hand, and if Mr. Petrofsky can call out to his brother
to run to him, we can take him up with us and get away before the
guards know what we are doing."

"But aren't the prisoners chained?" asked Tom.

"No, they depend on guards to prevent escapes."

"Then we'll try that way," decided the young inventor.

On and on they sailed, the Falcon working admirably. Verst after verst
was covered, and finally, one morning, Mr. Borious, who knew the
country well, from having once been a prisoner there, said:

"We are now near the place. If we go any closer we may be observed. We
had better remain hidden in some grove of trees so that at nightfall we
can go forth to the rescue."

"But how can we find it after dark?" asked Ned.

"You can easily tell by the lights in the barracks," was the answer. "I
can stand in the pilot house to direct you, for nearly all these exile
prisons are alike. The prisoners will