Securing these the two stepped out into the passage, locked and bolted the door; then Jack, who knew his way, proceeded along the passage to the stairway, leaped nimbly up the steps, bolted the door leading to the military quarters, then descended and bolted the bottom door.

“Now for the clerk, and then for the Governor.”

The clerk’s room connected with the armory, which was reached by passing through the apartment that held turbine and dynamo, which they found purring away merrily.

Covering the frightened clerk with four revolvers, Jack told him in Russian that if he made a sound it would be his last. They took him, opened cell Number Three, which was empty, and thrust him in.

Jangling the keys, the two entered the Governor’s room. The ancient man looked up, but not a muscle of his face changed; even his fishy eyes showed no signs of emotion or surprise.

“Governor,” said Jack with deference, “although you are under the muzzles of a quartet of revolvers, no harm is intended you. However, you must not leave your place until you accompany us down to the boat, when I shall hand the keys over to you, and in cell Number One you will find gaoler and lantern man a little worse for wear, perhaps, but still in the ring, I hope. In Number Three your clerk is awaiting you. I go now to release your prisoners. All communication between yourself and the military is barred. I leave my friend on guard until I return from the cells. You must not attempt to summon assistance, or cry out, or move from your chair. My friend does not understand either Russian or German, so there is no use in making any appeal to him, and much as I like you personally, and admire your assiduity in science, our case is so desperate that if you make any motion whatever, he will be compelled to shoot you dead.”

The Governor bowed.

“May I continue my writing?” he asked.

Jack laughed heartily.

“Certainly,” and with that he departed to the cells, which he unlocked one by one, only to find them all empty.