"I'll see who it is," volunteered Mr. Petrofsky, and Tom looked toward the rack of loaded rifles, for that day a man, seemingly a wood cutter had passed close to the airship, and had hurried off as if he had seen a ghost.
The knock was repeated. It might be their friends, and it might be
But Mr. Petrofsky solved the riddle by throwing back the portal, and there stood the Nihilist, Nicolas Androwsky.
"Is there anything the matter?" asked the exile quickly.
"We have news," was the cautious answer, as the Nihilist slipped in, and closed the door behind him.
"News of my brother?"
"Of your brother! He is in a sulphur mine in the Altai Mountains, near the city of Abakansk."
"Where's that?" asked Tom for he had forgotten most of his Russian geography.
"The Altai Mountains are a range about the middle of Siberia," explained Mr. Petrofsky. "They begin at the Kirghiz Steppes, and run west. It is a wild and desolate place. I hope we can find poor Peter alive."
"And this city of Abakansk?" went on the young inventor.
"It is many miles from here, but I can give
