The natives came on with a rush. There were about two hundred of them, and they had arrived on several big sleds. The Esquimaux who had piloted the adventurers back to their ship had disappeared, for he knew he would be killed as a traitor if his tribesmen caught him. "Come on!" cried Bill to Tom and the boys. "Let's get aboard. We'll be killed!" "You can go!" shouted Jack. "I'm going to stay down here and free the ship from ice. That's the only thing to do." "I'll stay with you!" exclaimed Mark. Tom and Bill scrambled up the sides of the ship and disappeared into the cabin. The boys remained on the ice, partly under the airship, chipping and picking to free the bottom. With loud shouts and yells the Esquimaux surrounded the _Monarch_. The savages were armed with bows and arrows, and soon a shower of these missiles were shot toward the craft. Professor Henderson was in mortal terror lest one of the sharp weapons would pierce the gas bag, but, for some reason, the natives fired at the lower part of the ship. Andy and the two helpers were now ready to return the fire. Their guns rattled out and the reports caused the natives great astonishment. The first shots the defenders had fired over the heads of the Esquimaux, not wishing to kill them if they could help it. But though the reports caused a momentary falling back, the attackers soon rallied again, and shot a thicker cloud of arrows, some of which fell uncomfortably near. "Let 'em have it right in the faces this time!" shouted Andy. He took careful aim at the mass of natives who were advancing, and one fell. Bill and Tom followed his example, and the onslaught was checked for a time. But now reinforcements to the Esquimaux arrived until there were fully five hundred of the fur-clad savages out on the ice surrounding the airship. To cope with such a force seemed madness. Bill received a slight wound in the arm, and Tom had a narrow escape from being killed, a big spear just missing his head. "Drop down below the rail!" yelled Andy. "They can't hit us so easy then, and we can fire just as good!" The defenders dropped flat to the deck, outside of the cabin. A loud yell on the part of the Esquimaux told that they thought the adventurers had been killed, and there was a rush to capture the ship. "Let 'em have it! As fast as you can pull the triggers!" cried the old hunter. "We'll show 'em what we can do!" The three guns rang out again and two of the natives fell, both badly wounded. "I wish we had more help!" exclaimed Andy. "We're likely to have trouble soon! Why don't those boys come up; in a few minutes they won't have a chance!" Indeed it would have been risky now for Jack and Mark to venture out from under the ship, where they were still bravely chipping at the last remaining bit of ice that help the ship fast. So far their presence had not been noted by the enemy. At that instant Professor Henderson ran out of the engine room.