e when I called you up. Dad is locked in the observatory with
Professor Nachbaren and three or four other men and the servants--well,
they all are so terrified that it simply alarms me to have them
around."

"But that is Stanton's plane there, isn't it?" asked Dirk, indicating a
powerful looking machine that stood on the terrace.

* * * * *

"Yes, Dirk," the girl replied. "He arrived here three or four minutes
before you did. I thought, at first, that it was you coming. And Dirk,"
she continued, with a note of excitement in her voice, "he flew up to
look at that thing, and I know that he is as frightened about it as I
am."

Dirk grunted, but he gave no expression of the dislike and distrust that
Stanton aroused in him. The latter, he knew, was very much inclined to
look with favor on Inga, and his presumption annoyed Dirk because, while
he and the girl had not declared their intention of living together,
they were very much in love with each other.

"You will want to hear him tell about it, I know, Dirk," the girl said.
"I left Stanton up on the garden terrace when I saw you coming down.
Come; we will go and join him."

Dirk and Inga strolled slowly along paths which were lined with exotic
shrubbery and plants. Here and there a fountain tossed its glittering
spray high into the air while birds, invisible in the feathery foliage,
warbled and thrilled entrancingly. Soft music, transmitted from the
auditoriums below, blended so harmoniously with the atmosphere of the
terraces that it seemed to mingle with and be a part of the drifting,
subtle scents of the abundant flowers which bloomed on every side.

For these upper terraces of Fragoni's palace were enclosed, during
inclement weather, with great glass plates which, at the touch of a
button, automatically appeared or disappeared.

Winding their way easily upward, Dirk and Inga came finally to a
secluded terrace which overlooked the Sound. Here they saw Stanton, who
was unaware of their approach, looking skyward at the dim and sinister
shape which was outlined against the sky. Stanton's brow was contracted
and his expression was filled with apprehension. He started suddenly
when he became conscious of the presence of Dirk and the lovely daughter
of Fragoni.

He rose to his feet, a short man in his forties, stocky in build and
somewhat swarthy in complexion. He contrasted very unfavorably with
Dirk, who was tall and well-built and w