"Yes. Brookfield is an odd genius who has invented a way of driving his forty-ton boat by horse-power against the river-current. He is at Louisville now, taking contracts for his next trip down the river, and sails next month."

"Well, see here!" Norton felt the fever gripping him again, but had already glimpsed a plan of action. "You get back to Louisville, see Elisha Ayres, and tell him about it. Ayres will communicate with me at Blue River."

"And you——!" queried the astonished Audubon.

"I'll trail that devil of a Grigg," said Norton hastily. "He said he was going to meet 'the boys', and if I can find their cache we'll nab the whole gang! By thunder, Audubon, we've the whole thing in our hands now!"

"But—wait!" cried Audubon hastily, as Norton turned toward the trail. "First, get this man Red Hugh! If he's a hunter, as Boone said, then you and he together will have no trouble picking up Grigg's trail, and you may need another rifle badly."

For a moment Norton considered this, while the fever swirled through him. He was sorely tempted to plunge off on the trail of Abel Grigg, but knew that there was sound advice in Audubon's words.

"All right," he said shortly. "Come—we'll find Red Hugh first."

His excitement overbore his illness for the moment, and returning to the trail he led the way to the very crest of the knoll. Duval and Grigg had been swallowed up in the forest, but staring them in the face was a giant cottonwood, blazed north and south. Pointing to it silently, Norton wheeled and headed away from the river into the trees.

How far they went through that wilderness he never knew, for after ten minutes he was fighting desperately against the pain and sickness which came over him. Worse than all, he was growing terribly weak; once he caught himself reeling, and only by a great effort did he keep on. Audubon had a small compass, by which they held directly south as Boone had commanded.

Then, almost without warning, Norton felt his knees giving way. He was very clear-headed, but he seemed to have lost the power of motion. With a single low groan he caught at a tree, missed it, and plunged down. Audubon was over him on the instant, raising him against the tree, dread anxiety in face and voice.