"Has anything happened?" asked Tom. "Are we suspected? Have they come to warn us?"

"No, everything is all right, so far," answered Ivan Petrofsky. "I didn't have the success I hoped for, and we may have to wait here for a few days to get news of my brother. But these men have been very kind to me," he went on, "and they have ways of getting information that I have not. So they are going to aid me."

"That's right!" exclaimed the one who had first spoken. "We will yet win you to our cause, Brother Petrofsky. Death to the Czar and the Grand Dukes!"

"Never!" exclaimed the exile firmly. "Peaceful measures will succeed. But I am grateful for what you can do for me. They heard me describe your wonderful airship," he explained to Tom, "and wanted to see for themselves."

The Nihilists were made welcome after Mr. Petrofsky had introduced them. They had strange and almost unpronounceable names for the ears of our friends, and I will not trouble you with them, save to say that the one who spoke English fairly well, and who was the leader, was called Nicolas Androwsky. There was much jabbering in the Russian tongue, when Mr. Petrofsky and Mr. Androwsky took the others about the craft, explaining how it worked.

"I can't show you the air glider," said Tom, who naturally acted as guide, "as it would take too long to put together, and besides there is not enough wind here to make it operate."

"Then you need much wind?" asked Nicolas Androwsky.

"The harder the gale the better she flies," answered Tom proudly.

"Bless my sand bag, but that's right!" exclaimed Mr. Damon, who, up to now had not taken much part in the conversation. He followed the party about the airship, keeping in the rear, and he eyed the Nihilists as if he thought that each one had one or more dynamite bombs concealed on his person.

"Ha!" exclaimed Mr. Androwsky, turning suddenly to the odd man. "Are you not one of us? Do you not believe that this terrible kingdom should be destroyed--made as nothing, and a new one built from its ashes? Are you not one of us?" and with a quick gesture he reached into his pocket.

"No! No!" exclaimed Mr. Damon, starting back. "Bless my election ticket! No! Never could I throw a bomb. Please don't give me one." Mr. Damon started to run away.

"A bomb!" exclaimed the Nihilist, and then he drew from his pocket some pamphlets printed in Russian. "I have no bombs. Here are some of the tracts we distribute to convert unbelievers to our cause," he went on. "Read them and you will understand what we are striving for. They will convert you, I am sure."

He went on, following the rest of the party, while Mr. Damon dropped back with Ned.

"Bless my gas meter!" gasped the odd man, as he stared at the queerly-printed documents in his hand. "I thought he was going to give me a bomb to throw!"

"I don't blame you," said Ned in a low voice. "They look like desperate men, but probably they have suffered many hardships, and they think their way of righting a wrong is the only way. I suppose you'll read those tracts," he added with a smile.

"Hum! I'm afraid not," answered Mr. Damon. "I might just as well try to translate a Chinese laundry check. But I'll save 'em for souvenirs," and he carefully put them in his pocket, as if he feared they might unexpectedly turn into a bomb and blow up the airship.

The tour of the craft was completed and the Nihilists returned to the comfortable cabin where, much to their surprise, they were served with a little lunch, Mr. Damon bustling proudly about from the table to the galley, and serving tea as nearly like the Russians drink it as possible.

"Well, you certainly have a wonderful craft here-- wonderful," spoke Mr. Androwsky. "If we had some of these in our group now, we could start from here, hover over the palace of the Czar, or one of the Grand Dukes, drop a bomb, utterly destroy it, and come back before any of the hated police would be any the wiser."

"I'm afraid I can't lend it to you," said Tom, and he could scarcely repress a shudder at the terrible ideas of the Nihilists.

"It would never do," agreed Ivan Petrofsky. "The campaign of education is the only way."

There were gutteral objections on the part of the other Russians, and they turned to more cheerful subjects of talk.

"What are your plans?" asked Tom of the exile. "You say you can get no trace here of your brother?"

"No, he seems to have totally disappeared from sight. Usually we enemies of the government can get some news of a prisoner, but poor Peter is either dead, or in some obscure mine, which is hidden away in the forests or mountains."

"Maybe he is in the lost platinum mine," suggested Ned.

"No, that has not been discovered," declared the exile, "or my friends here would have heard of it. That is still to be found."

"And we'll do it, in the air glider," declared Tom. "By the way, Mr. Petrofsky, would it not be a good plan to ask your friends the location of the place where the winds constantly blow with such force. It occurs to me that in some such way we might locate the mine."

"It would be of use if there was only one place of the gales," replied the exile. "But Siberia has many such spots in the mountain fastnesses--places which, by the peculiar formation of the land, have constant eddys of air over them. No, the only way is for us to go as nearly as possible to the place where my brother and I were imprisoned, and search there."

"But what is that you said about us having to stay here, to get some news of your brother?" asked Tom.

"I had hoped to get some information here," resumed Mr. Petrofsky, "but my friends here are without news. However, they are going to make inquiries, and we will have to stay here until they have an answer. It will be safe, they think, as there are not many police in town, and the local authorities are not very efficient. So the airship will remain here, and, from time to time I will go to the village, disguised, and see if any word has come."

"And we will bring you news as soon as we get it," promised Mr. Androwsky. "You are not exactly one of us, but you are against the government, and, therefor, a brother. But you will be one of us in time."

"Never," replied the exile with a smile. "My only hope now is to get my brother safely away, and then we will go and live in free America. But, Tom, I hope I won't put you out by delaying here."

"Not a bit of it. More than half the object of our trip is to rescue your brother. We must do that first. Now as to details," and they fell to discussing plans. It was late that night when the Nihilists left the airship, first having made a careful inspection to see that they were not spied upon. They promised at once to set to work their secret methods of getting information.

For several days the airship remained in the vicinity of the Russian town. Our friends were undisturbed by visitors, as they were in a forest where the villagers seldom came and the nearest wood-road was nearly half a mile off.

Every day either Mr. Petrofsky went in to town to see the Nihilists or some of them came out to the Falcon, usually at night.

"Well, have you any word yet?" asked Tom, after about a week had passed.

"Nothing yet," answered the exile, and his tone was a bit hopeless. "But we have not given up. All the most likely places have been tried, but he is not there. We have had traces of him, but they are not fresh ones. He seems to have been moved from one mine to another. Probably they feared I would make an attempt to rescue him. But I have not given up. Me is somewhere in Siberia."

"And we'll find him!" cried Tom with enthusiasm.

For three days more they lingered, and then, one night, when they were just getting ready to retire, there was a knock on the cabin door. Mr. Petrofsky had been to the village that day, and had received no news. He had only returned about an hour before.

"Some one's knocking," announced Ned, as if there could be any doubt of it.

"Bless my burglar alarm!" gasped Mr. Damon.

"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 you a good map," said the Nihilist. "Some of our friends are there," he added with a half-growl. "I wish we could rescue all of them."

"We'd like to," spoke Tom. "But I fear it is impossible. But now that we have a clew, come on! Let's start at once! It may be dangerous to stay here. On to Siberia!"