"It cer-certainly looks like a-a ghost!" faltered Cuffer. "It is a ghost!" said Tad, his teeth beginning to chatter. "I-I ca-can hear it gro-groan! Come on ba-ba-back!" And he began to retreat. "Back with you!" came in solemn tones. "Back with you!" "No white man must come here," said a second voice. "This is sacred ground!" "He who sets foot here dies!" came from a third voice. "This is the burial place of the great Hupa hupa! Back, if you value your life!" And then followed a jabbering nobody could understand, and white arms were waved wildly in the air. This warning was too much for Tad Sobber, and without further ado he took to his heels and retreated down the trail whence he had come. Cuffer followed him, and Shelley also retreated several yards. "Stop, you fools!" cried Sid Merrick. "Those are no ghosts, I tell you. It's a trick of some kind." "I--I don't know about that," answered Shelley. "Don't you think it would be better to come here in the daylight? We--er--we can't find that cave in the dark anyway." "Yes, we can--and I am going to do it, too," was Merrick's answer. "That is a trick, I tell you." He raised his voice: "Who are you?" he called out. "Answer me truthfully, or I'll fire on you!" This threat alarmed the Rover boys, for they saw that Merrick was in earnest. "I guess our cake is dough," muttered Tom. "Wait, I think I can scare him back yet," said Dick. "Let me do the talking." "I say, who are you?" repeated Merrick. "You needn't pretend to be ghosts, for I don't believe in them." "We are the owners of this isle," answered Dick, in the heaviest tone he could assume. "We are ten strong, and we order you to go back to your ship at once." "The owners of this isle?" "Yes." "I don't believe it." "You can do as you please about that. But if you come a yard further we'll fire at you." "Humph! Then you are armed?" "We are and we know how to shoot, too." "What brought you here at such a time as this?" "We have a special reason for being here, as you may learn by to morrow." "Do you know anything of a treasure on this island?" went on Sid Merrick curiously. "We know something of it, yes. It belongs to the Stanhope estate, provided it can be found." "It doesn't belong to the Stanhopes at all--it belongs to me," cried Merrick. "In a day or two the Stanhopes are coming here to take possession," went on Dick. "They will bring with them a number of their friends and uncover the treasure, which is now hidden in a secret place. As I and my brothers and cousins own this isle we are to have our share of what is uncovered. Now we warn you again to go away. We are ten to your four, and we are all armed with shotguns and pistols, and we have the drop on you." "Good for you, Dick, pile it on," whispered Tom. Then he pulled Sam by the arm. "Come on, let us appear from behind another rock--they'll think we are two more of the brothers or cousins!"