although the two physicians were deeply interested in the question of toxicology they could not forget their situation and its perils. the craft had nearly completed its half mile to the mouth of the tributary which it was intended to ascend, when the polemen, pausing for a moment's rest, whispered that they heard the sound of paddles again.

"there they are!"

it was jack everson who uttered the exclamation, loud enough for all to hear. he pointed down stream as he spoke, and every one perceived the dreaded boat returning.

although nearer at hand than before, it seemed to be following the course of the river, and there was hope that it would again pass without discovering the shrinking ones so near land.

when first observed the other boat was fifty yards out and not quite so far down stream. moving against the current its progress was slower than before, but its advance was plainly perceptible. the craft of the white people had lost the momentum imparted by the poling, and was now controlled only by the current, which was so sluggish close to the land that the motion was hardly noticeable.

the hopes of our friends steadily rose until the other boat was almost directly abreast. it would seem that if the occupants intended attacking they would have veered inward before this, but there could be no assurance so long as they remained visible.

every one started when the gaunt, sloping figure suddenly became upright at the prow of the boat and stood motionless. he had ceased using the pole that he had been plying with so much vigor. at the same moment the noise of the paddles ceased, proving that the men controlling them had also stopped work. what could it mean?

no one of the white people stirred or whispered. could they have done so they would have checked the beating of their hearts through fear of being betrayed. surely something had awakened the suspicion of the natives.

suddenly some one spoke on board the craft. the voice was audible, but the doctor, who was a master of hindoostanee, could not catch what was said. at the same instant a splash was heard, and the lank form bent over, as he pressed the long pole against the bottom of the river and resumed his slow walking toward the stern. the noise of paddles, too, was heard again. the craft had resumed its progress, and for an instant every one believed it was about to pass by. then jack everson said:

"by heaven! they're coming for us!"

all saw that the boat was swinging around so as to head toward them.

"into the cabin, quick!" commanded the doctor, and the women quickly scrambled out of sight, while the men lay down, so as to screen their bodies as much as possible.

"it won't do to let them come too near," added the physician. "try to make every shot tell."

as he spoke he took the best aim he could and fired. jack everson was but a moment behind him, and anderson discharged his gun almost simultaneously.