Two enormous birds landed on the ground near Tom and Bud.
       "They're after us!" Tom shouted in desperation.
       "We'll be pecked to death!" Bud said grimly. "I don't want to be on any vulture's menu!"
       "That's what Svornin had in mind," Tom replied.
       The boys struggled with the ropes that bound them. The harder they pulled, the deeper the cords cut into their flesh.
       "How about sawing our way out, Tom?" suggested Bud. "I have a pen knife in my pocket, and so have you. If only we can reach one, we'll have a chance to cut the ropes."
       Bud rolled over and over in the dust, trying to dislodge the knife from his pocket. Flapping wings told him he had scared off the two birds that had landed a few yards away. They rejoined the rest circling in the sky.
       Bud lay on one side, heaving from exertion. "Wow, am I glad those caranchos flew away," he said. "But they'll be back. And my penknife is still stuck in my hip pocket. Think of something, Tom."
       "I already have, Bud."
       Tom pulled himself up on his knees. Lowering his head, he flipped into a forward somersault. A metallic object fell from his breast pocket and lay gleaming in the sunlight.
       "You've done it!" Bud cried out.
       Tom rolled over, and though his hands were tied behind his back, managed to pick up the knife. He fumbled with the blade until it snapped open.
       Bud maneuvered his wrists into position near the knife. Holding the handle firmly, Tom pressed the cutting edge of the blade against the section of rope between Bud's wrists, and held it fast as Bud worked his hands back and forth.
       The sharp steel bit into the rope. First one strand broke, then another, and suddenly the bonds parted with a snap.
       "Thank goodness," Bud muttered. He quickly freed himself. Then he untied Tom. The boys stood up, rubbing their wrists to restore circulation. The vultures, seeing that Tom and Bud were no longer helpless, flew off.
       "Adiós, amigos," Bud murmured.
       Tom took out his pencil radio and contacted the Sky Queen, which was circling off the coast of Chile. He described a rocky protuberance shaped like a horse's head on the Strait of Magellan. He had noted this landmark during the flight to Tierra del Fuego.
       "We're headed there right now," he informed the Flying Lab's radioman. "Bud and I expect to have the galaxy ghost with us when we arrive. Order the seacopter to rendezvous with us. Tell the pilot to stay until we're aboard."
       The seacopter was Tom's combination flying and underwater craft. It could take to the air like a helicopter, and plumb the depths of the ocean like a sub.
       "Another thing," Tom went on. "We'll need a can of Soluweb."
       This was a revolutionary liquid spray he had concocted in his laboratory at home. Soluweb––consisting of two liquids that were mixed in spraying––was so powerful it could dissolve any metal, alloy or plastic, even the super-durable Tomasite.
       "Roger," came the response from the Sky Queen. "Don't sign off yet. We have some news."
       "Where's it from?"
       "Your father. He found the mastodon on the floor of the Pacific, and is about to begin rescue operations with the Sea Dart."
       "Great! What else is there?"
       "A report from Swift Enterprises. The university has nearly completed the receiving tank for the mastodon."
       "Perfect!" Tom exclaimed. "I'll use the Transmittaton if it's necessary. Anything else?"
       "That is all."
       "Roger. Signing off." Tom returned the pencil radio to his pocket.
       "I got the gist of the conversation," Bud said. "Now we're going after the galaxy ghost."
       "Correct, pal. These horse tracks left by Svornin and Company are worth following. They should lead us to the estancia and the pasture."
       The boys walked for about an hour. Just when they lost the hoofprints on stony terrain, they ran into a herd of sheep and two shepherds on horseback. The men had a couple of extra ponies which they agreed to rent. Tom promised to leave the mounts at Horsehead Point on the strait.
       "We're trying to catch up to a group of riders," Tom said. "Have you seen them?"
       "Sí," replied one of the shepherds. He pointed southwest. "They went into the valley between those two hills. I think they were headed for the estancia on the strait. Go that way. You cannot miss it."
       Tom and Bud mounted the ponies and galloped off. Some hard riding brought them by nightfall to the outer fence of a sheep ranch.
       Tom slowed to a walk, guided his pony into a copse, and dismounted. Bud followed. They tied their mounts, parted the leaves, and surveyed the lay of the land. Some distance ahead they could see the lights of a low sprawling building.
       "We'd better not move any closer to the ranch house," Tom advised.
       "No problem," Bud answered. "We can circle around and get into the pasture form the opposite direction. Then all we'll have to do is find the carrier. If the ghost is still where Svornin put it, we should be able to scoop it up and get away before the Brungarians know we've escaped."
       "Our first clue will be the bleating of sheep," Tom said as they gave the ranch house a wide berth and reached the pasture.
       "I hear them over there." Bud pointed to a stretch of pasture behind the shearing shed. "Let's try that tall rocky grotto. It's what I'd choose for a quick hiding place."
       "So would I. Come on, Bud. We'll find out whether it's really the spot where they stopped before escorting us out onto the pampas."
       The boys strode through the pasture between the sheep, and entered the grotto. Bud turned on his flashlight. Rocks and boulders littered the ground. Stony walls ten feet high formed a three-sided room with an opening which faced the pasture. Here and there hardy flowers pushed through crevices, clinging by their roots to what little soil there was in which to grow.
       "I don't see––" Bud started to say.
       "Psst! Up there!" Tom interrupted him. "That object on the ledge covered by a blanket! It's the right size and shape!"
       The boys clambered to the ledge. Tom jerked off the blanket.
       The Tomasite carrier with the pulsating P-E was revealed.
       "We have the ghost back." Tom grinned in relief. "Now to get it away safely."
       "I hear hoofbeats!" Bud warned. "Somebody's outside the grotto!"
       Loud yelling erupted. Bud jumped down, ran out, and saw a horseman galloping toward the ranch house. Tom followed, carefully carrying the ghost with him.
       "Help! Help!" the man shouted. "Thieves!"
       "He spotted us!" Bud exclaimed. "There's only one thing for us to do now––leave a lot faster than we came."
       Tom and Bud ran across the pasture at top speed, reached the copse, and untied their mounts. They vaulted into the saddle and galloped off.
       "Head for the high rocks along the strait," Tom called, holding the carrier tightly under one arm. "We'll be able to reach Horsehead Point where the seacopter is due to arrive. It might even be there now."
       Bellowing voices echoed behind them. Hoofbeats clattered over the gravel. Looking back, they saw four riders cutting through the gully, obviously determined to head off the fugitives before they could reach the strait.
       Tom pivoted his mount on its hind legs. "Come on, Bud. This is a race for life!"
       Loosening the reins, he urged his pony toward a pile of rocks, cleared them in a single bound, and rode headlong across a level space between two mounds.
       On the opposite side was a steep ravine. Holding his pony back on its haunches with a firm hand, and maintaining his grip on the ghost carrier, Tom negotiated the slope in a series of plunging descents that sent the earth flying from under the horse's hoofs. Slackening the reins again, he charged full tilt out of the ravine toward Horsehead Point. High above he saw the blinking lights of the seacopter.
       Meanwhile, Bud took an alternate route. He rode skillfully along a ledge with a sheer drop of fifty feet on one side. He leaped a series of dead tree trunks and rejoined Tom beyond the ravine for the final dash toward the summit.
       At the edge of Horsehead Point, Tom and Bud threw themselves from their ponies. Scrambling up the rock, they saw the seacopter scouting the area in search of them.
       Bud began to signal frantically with his flashlight. Tom made contact by means of his pencil radio. The seacopter pilot saw them and zoomed in their direction. A rope ladder was lowered from the craft.
       By now the Brungarians had reached the foot of Horsehead Point. They came scrambling up in hot pursuit.
       The ladder from the copter did not quite reach the rock, but dangled out over the water. Tom could not wait for the pilot to maneuver closer. He leaped out from the rock and caught hold of the ladder with one hand. Clutching the handle of the ghost carrier with the other hand, he began to climb up.
       Looking back, Tom could see their pursuers reaching out for his pal.
       "Bud! Jump!" Tom shouted.