's
deadly rifle. One of the unfortunate negroes had thoughtlessly broken
his resolve and had spoken. He had paid dearly for his mistake. Under
the stern command of the rifle muzzle the others renewed their task,
glancing apprehensively at the man behind the grim weapon whose
messengers were all messengers of swift and certain death. They were
visibly affected.

Instinctively the boys drew their automatics while Harrison possessed
himself of his revolver and made ready to use it if necessary in self
defense. No one could guess the result should Lopez discover their
whereabouts. Their position was now seen to be a most dangerous one, for
they lay but a few yards beyond the rim of the excavation in which the
men were working. Lopez was opposite.

"If that man ever sees us here," whispered Harry, "we're gone."

"You're right, we're gone," declared Arnold. "That man don't think any
more of shooting a man than he did of shooting that big snake. He's
absolutely bloodless, I believe."

"Look at Wyckoff down in the excavation walking back and forth and
around," Tom said pointing to the figure mentioned.

"He surely isn't going to let anything get past him," agreed Jack. "He
walks round and round and round as the men dig."

"And they are digging at a rapid pace, too," Frank put in. "At that rate
they ought to get the treasure before long."

"I'm a little afraid," Harrison dissented. "It looks bad."

"What looks bad? The two men may quarrel."

"There's always a possibility of that," agreed Harrison, "but I wasn't
thinking of that. It looks to me that the sand will probably be softened
by the rising tide. If so, they can't remain in the excavation to dig
for the treasure at all. They must quit."

"If that happens, I can see some more dead niggers," Tom asserted. "That
man Lopez seems to be itching to shoot someone. If he is foiled in his
last desperate attempt to get that treasure, I can see trouble ahead for
someone who is near him when it happens."

Wyckoff now came out of the hole to join Lopez on the rim of the crater
made by the toiling negroes. Without saying a word he evidently asked
Lopez for something to drink, for he made a motion as if drinking from a
cup, Lopez without taking his eyes off the workers jerked his head in
the direction of the boat.

"Now what?" asked Frank in wonderment. "Is he thirsty?"

"I don't think so," replied Arnold. "I believe he's going after
something to stimulate the shovelers. T