After they had left the beach well behind, the chums strolled in under the trees of a rather sparse grove.

Well in toward the center of the grove stood one tree larger than the rest.

From behind this Sambo Ebony swiftly appeared, just at the right instant for surprise.  In each hand the negro held a huge automatic revolver.

“Gemmen,” chuckled the negro coolly, “Ah jess be nacherally obliged to yo’ both if yo’ll stick yo’ hands ez high up in de air ez yo’ can h’ist ’em.  It am a long worm dat nebber turns, an’ Ah’se done reckon dat Ah’se de tu’ning worm to-night!  Thumbs up, gemmen!”

Despite Sambo’s bantering tone there could be no doubt that to fail to obey him would be to invite a swift fusillade.

Reluctantly Tom Reade thrust his hands up skyward.  Nor did Dick Prescott hesitate to follow so prompt an example.

CHAPTER XXIV

CONCLUSION

“Now Ah reckon Ah’se done got yo’,” laughed the big negro, insolently.  “It am a question ob w’ich one Ah wantah pick off fust!”

In his wicked joy over having both the young engineer and the army officer wholly at his mercy Sambo, his mouth open and his massive teeth showing white in his grin, advanced nearer.

Yet he did not fail to keep each of his enemies covered.  He was watching most alertly for any sign of rebellion on the part of his victims.

Nor was there any doubt in the mind of either young man that the black, after playing with them, meant to dispose of them as his possession of pistols indicated.

He would torment them first, then ruthlessly “shoot them up.”

“How long are we to keep our hands up?” asked Tom banteringly.

It would be foolish to say that Reade was not afraid, but he was determined to keep Ebony from discovering the fact.

“Yo’s to keep yo’ hands up longer dan yo’ can keep yo’ moufs shut!” scowled the black man, his ugly streak showing once more.

“It makes me think of the way we used to play football,” laughed Reade, though there was not much mirth in his chuckle.

“Shut yo’ mouf, or Ah done gib yo’ plenty to think erbout!” ordered Sambo angrily.

That word “football” set Dick Prescott to tingling.  He knew there was some hidden meaning in what Tom had said.

“Are you trying to signal us, Sambo?” queried the army officer.

That word “signal” was intended only for Tom’s ear, for Lieutenant Prescott was beginning to guess at the truth.

“On the gridiron, on the gridiron!” hummed Tom, audibly, as he tried clumsily to fit the words to the refrain of a popular song.

Dick Prescott was “getting warm” on the scent of the hidden meaning.

“Shut yo’ mouf!” gruffly commanded the lack.  “Ah doan’ wantah tell yo’ dat again, neider.”