"That is just it," Bob remarked, "and you remember what Daniel Boone warned us against. This must be that terrible Simon Girty, or his companion, McKee, for if you look once again, you will see those forms concealed behind the grass and bushes, just as the panther lies in wait for a deer at the salt lick. Is that all plain to you, Sandy?" "Yes, and I would have seen through it, even if you hadn't spoken. But here, for the third time, we have received a message from this friend, who keeps his face hidden, so that we do not know who he is. What does it mean, do you think, and who can he be?" "He must have some object," replied Bob, his brow marked by a line of perplexing thought; "and he certainly has a reason for not letting us know who he is. If it is that young Delaware you helped, he has a queer way of paying back his debt. But, after all, he is only an Indian, and how can a white man understand his ways? We must show this to father, even if it doesn't seem to tell us anything new." "Yes," said Sandy, drawing a long breath, and glancing at the forest so close at hand; "anyhow, it's nice to know we've got a friend who watches over us all the time. There may come a day when his warning will save us from a terrible danger. Delaware brave or not, I am going to thank him for it, if ever I meet him face to face." As they had already been told all about these perils, the men did not experience any fresh alarm from seeing the message of the arrow. Mr. Armstrong, thinking it wise to keep all such causes for uneasiness away from the women as much as possible, bade the boys not to mention finding it on the roof. Plainly the unknown Indian must have shot it from some point close at hand, though how he had managed to approach the boat, unheard by the keen, listening ears of Blue Jacket or Pat O'Mara, was a mystery to both Bob and Sandy. If he could do this, what was to prevent a dozen, or fifty, of his kind from accomplishing the same thing? It was a thought calculated to cause a timid person considerable uneasiness; and possibly this was what had influenced Mr. Armstrong in his desire to keep the women from hearing about the arrow that bore the new warning. Again they were floating on the current, that bore the adventurers along at the rate of some four miles an hour. While the river changed its course from time to time, so that they headed now southwest, and again toward the northwest, still their constant progress was such that they had the morning sun behind them; and, when the orb of day passed the zenith, it beckoned them onward until, nearing the horizon, its slanting rays warned them that another night lay ahead, with the dangers that darkness must ever bring in its train. And so it would go, as the days slipped by, many miles being covered between daybreak and darkness, and each span taking them further into the unknown country. CHAPTER XIII BLUE JACKET GIVES WARNING THREE days had now passed.