his request the tug was put under way and the "Betsy B." started back
to her home port in Key West. During the trip Tom managed to cut from
the meteorite a fifty-pound chunk.

[Illustration: Tom Cut off a Large Chunk]

"I'm very eager to see if this stone contains more X," he explained to
Ned, "so I'm planning to fly straight home with this sample to analyze
it. I want you to put the rest of the meteorite on a fast freight train
and travel north with it."

The sun was setting when the dock at Key West was reached. Tom waited no
longer than was necessary to take on a supply of gasoline for the
"Winged Arrow." He paid Captain Britten a generous fee and added a bonus
for the divers who had helped him. Then with a hasty good-bye the
excited young inventor roared off in the gathering darkness toward his
distant home.

[Illustration: He Paid Captain Britten]

After an uneventful flight he reached Shopton at about half-past one the
following morning. The wheels of the plane had barely stopped turning
when the tall figure of Koku came rushing out of the shadows of the
hangar to greet his master.

[Illustration: Koku Came Rushing Out]

"You're right on the job!" exclaimed Tom, climbing stiffly from the
cabin. "How is everything?"

"All thing good!" declared the giant, grinning to see the young inventor
back. "Catchum skystone?"

"We caught it, all right. You might tote this sample of it over to the
lab." Tom handed his servant the segment he had chiseled from the main
mass.

"Master knows 'bout secret cave under lab'tory?" questioned the giant as
the two walked across the field in the moonlight.

[Illustration: "Tote This Sample to the Lab."]

"Cave? Oh, you mean the vault?" asked Tom, who had been thinking of
other matters.

"Night you go 'way in sky-bird, Koku watch. Koku hear bell go
ting-ting-ting!"

Suddenly Tom was paying strict attention.

"Great Scott! D'you mean to say someone broke into my Chest of Secrets?
Tell me about it quickly!"

[Illustration: Tom Paid Strict Attention]

CHAPTER X

SUCCESS

"Me tell!" said Koku. "Hear bell, know bad mans hide in cave. I creep up
an' watch!" His dramatic pause might have seemed funny at any other time
but Tom was badly worried.

[Illustration: Tom Swift Was Worried]

"Hurry up!" commanded the young inventor sharply, grabbing the giant's
arm. "What happened?"

"Nothing happen US," answered Koku. "Plenty happen HIM! I catchum fella,
crawl up