With renewed vigor the work was again taken up.
"If this keeps up," declared Arnold fretfully, "those fellows will have all the coin in a minute and not leave any for us."
"Keep your temper," Jack cautioned. "Something may happen--"
The lad was interrupted by a blinding flash, followed by a roar as if one of the old Spanish cannons had exploded beside them.
A shower of sand fell over the boys concealed behind the clump of palmettos. Instinctively they all drew closer their fellows.
The ground shook beneath them while all around it seemed to be raining sand. As they looked at the spot again they could make out but two figures standing. Wyckoff and Lopez were on opposite sides of the pit. The negroes were nowhere to be seen.
Wyckoff's face was cut and bleeding while Lopez seemed to have had his clothing bodily torn from the upper part of his body.
"What do you know about that?" queried Jack. "What was it?"
"An earthquake," suggested Charley, "or a volcano."
"Volcano nothing," stoutly corrected Arnold. "That was the dynamite that Wyckoff planted on the Fortuna in Pascagoula and Jack stumbled over it and brought it here and we planted it a moment ago."