Knowing how stubborn Dick could be when he knew that he was wholly right, Dave lost no time in argument. He sprinted away, and presently Dick heard faint echoes of Darry's signaling, "hoo-hoo!" A few minutes later the trio came up at a dog trot. Not one of them spoke, as all had lost their breath in their haste. Tom, now in the lead, dashed up to where Dick stood on guard a few yards away from the bushes. "Over there," nodded Dick, pointing to the bushes. Tom and Dan pulled the bushes aside curiously. "If we're going into that cave we may as well cut the bushes down," murmured Reade, producing a pocket knife. "Any objections, Chief?" "No," smiled Dick, "and I'm not the Big Chief, either. Cut the bushes down, if you want. Move over, and I'll give you some help." Within a short time the bushes had been cut down close to the ground, revealing an irregular shaped opening in the cave. This aperture was about three feet high and some five feet in width. "Did you bring that pocket flash lamp, Tom?" asked Dick suddenly. "Thank goodness, I did," replied Reade, producing the lamp. Dick took it and crawled a few feet into the hole. "There's water all along on the floor here," he called, "but just a dribble. Come in here and you'll find that you can stand up." It needed no urging to induce the other boys to follow. Then they stood up, in almost complete darkness, save when the flashlight showed them their surroundings. Some parts of the cave rose to a height of perhaps sixteen feet. Twelve feet was about the average height. From what the boys could see as they moved along, the cave extended for some sixty feet. "I don't believe there's anyone in here except ourselves," muttered Darry in disgust, peering all around him. "In that case, we are wasting our time in this cave. Phew! How cold it is in here!" "And well it might be," laughed Dick. "Do you see that mass just ahead of us?" "What is it?" asked Dan. "Flash the light on it." "Come over and look at it," Dick went on. "No one could live in this cold place. It is chilling me to the bone, just to stand here. And now you see why that little trickle of water keeps moving out through the mouth of the cave. Fellows, we're in one of nature's icehouses." "But we're not after ice," Dave protested. "We won't turn down ice in the wilderness, when we can find it in July," Dick rejoined. "Not much!" answered practical Tom Reade. "Why, fellows, ice is just what we need at the camp. Let's get a closer look at it and make plans for an ice-box over at the camp." "But I want to follow that man of mystery," protested Dave. "Go ahead, David, little giant," Dick laughed. "We won't stop you. But we've lost our man of mystery, anyway, and this cave contains something that we really do want. Tom, you're the mathematician of the party. How much ice is there here?" "If I could see better I could tell you better," sniffed Reade. "Hundreds of tons of it, anyway."