minutes later Tom was alone in the office, which
appeared exactly as it had before he was rendered unconscious. Yet there
crouched in the vault a hidden spy whose purpose was as sinister as his
appearance.

[Illustration: He Draped the Rug Over the Door]

"Mist' Swift, Massa Tom ain' come back fum de office yit," announced Rad
Sampson as he placed the elderly inventor's nightly glass of hot milk on
the library table. "I wuz jest up t' his room to ax him suffin' an' he
wuzn't dar."

"Well, I guess the boy is working a bit late tonight. But you sound a
trifle anxious, Eradicate. Do you think anything is wrong?"

"Uh--Oh, no suh. No suh," mumbled the old Negro. "I jest wondered ef
yo'd seen him. Good night, suh! Good night!"

[Illustration: "Massa Tom Ain' Back Fum de Office."]

"Good night, Rad."

"Mustn't worry ole Mist' Swift," the servant muttered to himself as he
shuffled back to the kitchen. "But Massa Tom tole me hisself he gwine t'
baid early 'cause he gotta git up befo' sunrise.

"Look hyah, Koku," he went on when he got to the kitchen. "Quit stuffin'
dat 'ar pie an' go out an' see ef Massa Tom all right. He ought t' have
bin in de house long sence. I'se skeered mebbe some villains mought've
cotched him!"

[Illustration: "See Ef Massa Tom All Right."]

"Whoo!" growled the giant, jumping up so quickly that his big,
specially-built chair crashed over. "Where um war-club? Me fixum!"

"Doan make sich a racket, yo' big lummox! Yo' want to skeer ol' Mist'
Swift? Heah, take mah rollin'-pin."

Clutching the rolling pin as a "war-club," Koku started through the
darkness toward Tom's private laboratory. Following him at a discreet
distance came old Rad Sampson, who had armed himself with a big
butcher knife.

[Illustration: Rad Followed]

"Dar's a light in de office, big boy," whispered the Negro. "Be keerful,
now!"

The giant merely grunted, crept up to the window and peered within. His
great height enabled him to do so easily. "Come," he said finally,
turning toward the door. "We go in."

"Whut de matter?" demanded Eradicate, struggling to keep up with his
companion. "Am suffin' wrong? Mah goodness!" he cried a moment later
in the office. "Po' Massa Tom done been killed! Look at him a-layin'
dere!"

[Illustration: The Giant Peered in the Window]

"Him no dead!" rumbled Koku, leaning over his master. "Him heart still
beatum. Him need fresh air." Gently he picked Tom up and carried him
outside.

"