"Hold on--not that!" protested the prisoner, hoarsely. "Yes; even that!" mocked Eph, picking up a fragment of rock. "And keep quiet, unless you want me to batter your head in!" It was this rough, vigorous sea-talk, backed by a belief that young Somers would prove equal to his threat, no doubt, that made Millard allow his left wrist to be brought over to meet the right. "You've got those things on too tight," complained Millard, sullenly. "No-o-o, I don't think so," retorted Captain Jack, after looking. "We need 'em as tight as we can have 'em, without causing pain, when we have a fellow like you to deal with. Now, what was that explosion?" "Wait a second!" broke in Eph, in a low voice. "Millard had a pal here. It was the pal I shadowed here. And that pal is running, now, with a fair-sized bundle that he came here to get." "He was running when you jumped into this business?" demanded Benson. "Yes." "Then the pal is too far away, by this time, for us to catch him by running after him," decided Skipper Jack. "Now, about that explosion!" "This wretch had a mine planted up on the hill," explained Hal Hastings. "I was watching, at the rear, you know, and it happened that I stopped right close to the hollow where you found me. Then I saw Millard drop into that hollow, and I took a look-in. I was just in time to see him bending over to reach for the handle of a magneto battery. Now, I happened to know that magneto batteries are made for the purpose of touching off explosives at a safe distance. So I jumped in on him. Just at that second I heard you, Jack, old fellow, striking with the shovel up above there. I had to guess fast, so the whole thing struck me like a flash. Millard had been digging, up there, just to lead on anyone who might be shadowing him. While you were bent over the spot where he had been digging, he meant to touch off a mine that must have been planted and laid days ago. Millard, you rascal, if you suspected that you were being watched, it was your idea to lead the shadow out here, get him over that mine and touch it off!" The prisoner's eyes flashed. "That was your game, wasn't it?" demanded Benson, angrily. "Find out, if you can," growled the prisoner. "You've guessed it, Hal," nodded Jack, then shuddered. "Had I followed this villain out here alone, and then gone to digging, unwarned, where I had seen him digging, my remains would have come down in four counties. But, you mean scoundrel, you never happened to think that you'd be trailed by three different fellows, all at different points along your trail."