he was
trying to appear calm.

"Mr.--this gentleman's friend has returned from banishment, and----"

"Returned! has the wall been destroyed?"

"No; he accidentally discovered the danger, and came in a flying-machine
to warn you."

"Where is he? bring him to me, quick!"

"But you will not ----"

He waved his hand impatiently. "Go; if Alpha is saved he shall be at
liberty--if it is not, what does it matter?"

Thorndyke hastened away after Johnston, who, when he was told of the
king's words, readily accompanied his friend to the presence of the
ruler. They found him with his daughter still on the balcony.

"How did you discover this?" asked the king, turning to the American.

As quickly as possible, Johnston related his adventures, and
particularly the story of the shooting fountain and the fall of salt
water. The king did not wait for him to conclude. He ran back into his
chamber, touched another button, and the next instant alarm-bells were
ringing all over the city.

"A signal to the protectors," explained the princess to Thorndyke; "by
this time they are ringing all over Alpha. Oh, what will become of us?"
as she spoke she leaned over the balustrade and looked down into the
street. Vast crowds had gathered and were motionless, except at points
where the purple-clad "protectors" rushed from public buildings to
assemble in squads on the street corner.

Chapter XVII.

Bernardino turned to look after her father as he was leaving the room.

"He is going to the observatory," she said to Thorndyke and Johnston.
"Let us go also." And they followed the king into the room with the
glass roof and walls covered with mirrors which he had shown the
strangers several days before. A white-headed old man stood at the
stand, his fingers trembling over the half circle of electric buttons.
In a mirror before him he was studying the reflection of a town of
perhaps a hundred houses. The streets were filled with excited
citizens, and a squad of protectors stood ready for action near a row of
flying-machines.

"Ornethelo," said the king, and at the sound of his voice the old man
turned and bowed humbly.

"All right," went on the king, "I will take your place a moment."

He went to the stand and touched a button. Instantly the scene changed;
fields, forests, streams and hills ran by in a murky blur, and then
a larger town flashed on the mirror. Here the same stir and alertness
characterized the scene. The gaze of every