Soon after sundown they were on the move. As Nick Carter had remarked, there were rapids not far from where they had stopped for sleep, and it was necessary to carry the boat and stores around the cataract on land, and put it into the river again at a safe distance above. By the time this was accomplished, the night had advanced so far that Nick was afraid they would not make much more time before daylight. He was strengthened in this belief by the fact that the whole party was pretty well exhausted by the labor of getting the boat and stores around, and was obliged to rest. It had meant a walk of more than two miles, and everybody had been obliged to do his full part. The labor had been much heavier than Jai Singh had anticipated. It was easy for all of them to fall asleep. The slumber they had had in the daytime was not so refreshing as this, with blackness around them and even the ordinary voices of nature stilled. Chick had laid down by the side of the bloodhound, and was one of the first to lose himself. It had been arranged that they were to sleep for an hour and then go on. The others each dropped down into any attitude that seemed comfortable, and in a few moments all were as oblivious to the outer world as Chick himself. Suddenly a strange cry echoed through the blackness of the forest. It was a shriek of agony that echoed and reëchoed until it died away into a wailing moan. Hardly human, yet a sound that no animal could have produced. Captain heard it; Chick knew that by the way he stirred and whimpered. “What was that?” whispered Nick Carter. In the deep gloom, Chick could see the detective sitting up, ready for action, his rifle across his knees. “You heard it, did you?” asked Chick quietly. “It woke me.” “Hush!” The cry arose again, but was more faint than before. “What kind of game are they giving us?” muttered Jefferson Arnold. “Is it a screech owl?” Jai Singh, without speaking, picked up his spear and waited for what was to come. For the third time the scream sounded through the forest--long drawn out and ending in a sobbing wail. “It is the devils of the forest. There are unclean spirits walking near,” muttered Jai Singh. “Spirits or no spirits, clean or unclean,” said Nick Carter. “I am going to see.” He struck a match, but, so powerful was the ghostly influence even upon the detective’s usually steady nerves, that his hand shook, and he dropped the match. Perhaps he did not try much to hold it, for it seemed to him, even as the light broke out, that it was hardly a wise thing to do until he knew what was in the vicinity. “I have my flash light in my pocket,” he muttered to himself. “But, on the whole, I guess we’d better investigate in the dark.” From the four coolies, some two or three hundred feet away, there came no sound. Whether they had heard the cry or not Nick did not know. Certainly, they made no sign.