the younger Russian brother. "If the
gasolene is gone, how can we leave here?"

"Trust Tom Swift for that," was the reply. "Keep out of sight now,
there is a large crowd outside."

Tom came from the tank room. There was a despondent look on his face.

"It's all gone--every drop," he said. "That's what made the motor stop."

"What's gone?" asked Mr. Damon.

"The gasolene. We sprung a leak in the main tank, somehow, and it all
flowed out while we were flying along."

"Haven't you any more?"

"Not a bit. I was drawing on the reserve tank, hoping to get to
civilization before I needed more. But its too late now. We will have
to--"

"Bless my snow shoes!" cried Mr. Damon. "Don't say we'll have to stay
here--in Siberia! Don't say that. My wife--"

"No, we won't have to stay here if we can get a supply of kerosene,"
interrupted Tom. "The motor will burn that. The only trouble is that we
may be detained. The authorities probably know us by this time, and are
on the watch."

"Then get it before they know we are here," advised Ned.

"I'll try," said Tom, and he at once conferred with the elder
Petrofsky. The latter said he was sure kerosene could be had in town,
and, rather than risk going in themselves, they hired a wagoner who
agreed, for liberal pay, to go and return with a quantity. Until then
there was nothing to do but wait.

Meanwhile the crowd of curiosity seekers grew. They thronged around the
airship, some of them meddling with various devices, until Tom had to
order them away with gestures.

One particularly inquisitive man insisted on pulling or twisting
everything, until he happened to touch a couple of live wires, giving
himself quite a shock, and then he ran away howling. But still the
crowd increased, and at last Mr. Petrofsky said:

"I don't like this, Tom?"

"Why not?" They were all inside the craft, looking out and waiting for
the return of the man with the kerosene. The leak in the tank had
proved to be a small one, and had quickly been soldered. It had been
open a long time, which accounted for the large amount of gasolene
escaping. "What don't you like, Mr. Petrofsky?"

"So many men surrounding us. I believe some of them are officers
dressed in civilians' clothes, and a Russian officer never does that
unless he has some object."

"And you think the object is--?"

"To capture us."

"If it was that, wouldn't they have done it long ago--when we first
came down?"

"No, they are evi