Small wonder that Billy, as he hastily roused Lathrop, felt a
shudder run through him. He had heard enough from Frank of the ways
of Muley-Hassan to know that they could not well fall into the hands
of a more pitiless foe and that now, with the Golden Eagle gone and
the Boy Aviators already at the ivory cache, it was probable that
the slave-dealer's rage would render him even more savage than was
his wont.

In a few rapidly whispered words Billy apprised Lathrop of the
situation. Like Billy, the other boy had no lack of pluck but his
heart sank, as had his companion's, as he sensed the full meaning of
Sikaso's warning.

"But perhaps the smoke was mistaken," he said eagerly, willing to
grasp even at that straw of hope; but the old warrior's answer
dashed his aspirations to the ground.

"The smoke is never mistaken," he said simply; but with such calm
conviction that the boys, despite themselves, realized that the old
Krooman had really the knowledge of grave peril approaching.

"Had we not better arm the other Kroomen?" asked Billy anxiously.

"It would be useless," was Sikaso's reply, "they are cowards. At
the first sight of blood they would run to the forest like the sons
of weaklings that they are."

"We must rouse Professor Wiseman at once," cried Billy.