s and fled incontinently. Of the remainder a
few of the bolder spirits handled their rifles and looked inquiringly
at their officers. Mazanoff saw this, and at once raised his hand
towards the sky and shouted--

"Ground arms! If a shot is fired the Arsenal will be destroyed as
Kronstadt was, and then we shall attack Petersburg."

The threat was sufficient. A grey-haired officer in undress uniform
glanced up at the _Ithuriel_ and her consort, and then at the guns of
the _Ariel_, all four of which had been swung round and brought to
bear on the side of the building near which she had descended. He was
no coward, but he saw that Mazanoff had the power to do what he said,
and that even if this one air-ship were captured or destroyed, the
other two would take a frightful vengeance. He thought of Kronstadt,
and decided to parley. The rifle butts had come to the ground before
Mazanoff had done speaking.

"Order arms, and keep silence!" said the officer, and then he
advanced alone from the crowd and said--

"Who are you, and what is your errand?"

"Alexis Mazanoff, late prisoner of the Tsar, and now commander of the
Terrorist air-ship _Ariel_. I have not come to destroy you unless you
force me to do so, but to ask certain questions, and demand the
giving up of certain property delivered into your hands by deserters
and traitors."

"What are your questions?"

"First, is Professor Volnow in the building?"

"He is."

"Then I must ask you to send for him at once."

It went sorely against the grain of the servant of the Tsar to
acquiesce in the demand of an outlaw, but there was nothing else for
it. The outlaw could blow him and all his subordinates into space
with a pressure of his finger; and so he sent an orderly with a
request for the presence of the professor. Meanwhile Mazanoff
continued--

"An air-ship similar to this arrived here three days ago, I believe?"

The officer bit his lips with rage at his helpless position, and
bowed affirmatively.

"And certain articles were taken out of her for examination here--two
gas cylinders and a projectile, I believe?"

Again the officer bowed, wondering how on earth the Terrorist could
have come by such accurate information.

"And the air-ship has been sent on to the seat of war, while the
Professor is trying to discover the composition of the gases and the
explosive used in the shell?" went on Mazanoff, risking a last shot
at the truth.

The officer did not bow th