"I have seen it in the smoke," was the somber reply; "the smoke never lies. After I lay down on my skins I could not sleep, I felt there was danger approaching us. From where I knew not. So I made the "fetish" fire. In it I saw a band of men coming toward us down the river and at the head of them was a dark man—a man you know well, my white brother with the four eyes."
"Diego!" exclaimed Billy divining the other's thought.
"Yes, Diego; cursed be the day that my war-axe did not cleave his ugly skull; but beside Diego there is another. Hearken to the words of Sikaso, the elephant in his rage is not more merciless, the serpent not more cunning, the crocodile not more savage in onslaught than this other. He is Muley-Hassan, the Arab, and the deeds he has done, my brother, when recounted turn strong men's blood to water."
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.