To make each of them, he had taken a flask of compressed air from our emergency stores, and run a flexible tube from it into a cylindrical drinking water container. Another tube, which I recognized as being a part of our fire-extinguishers, and terminating in a metal nozzle, sprouted from the water container. Both tubes were securely sealed into the mouth of the metal cylinder, and lengths of hastily-knotted rope had been bound around each contrivance so that the two heavy containers, the air flask and the small water tank could be slung from the shoulders. "Here, sir," he said hastily, "get into a breathing mask, and put on these things as you see me do. No time to explain anything now, except this: as soon as you're outside the ship, turn the valve that opens the compressed air flask. Hold this hose, coming from the water container, in your right hand. Don't touch the metal nozzle. Use the hose just as you'd use a portable disintegrator-ray projector." I nodded, and followed his instructions as swiftly as possible. The two containers were heavy, but I adjusted their ropes across my shoulders so that my left hand had easy access to the valve of the air flask, and the water container was under my right arm where I could have the full use of the hose. "Let me go first, sir," breathed Hendricks as we stood again in the air-lock, and the door turned out of its threaded seat and swung open. "Keep your eyes on me, and do as I do!" * * * * * He ran heavily out of the ship, his burdens lurching. I saw him turn the pet-cock of the air flask, and I did likewise. A fine, powerful spray shot from the nozzle of the tube in my right hand, and I whirled around to face the ship. Several of the things were detaching themselves from the ship, and instinctively, I turned the spray upon them. Hendricks, I could see out of the corner of my eye, did likewise. And now a most amazing thing happened. The spray seemed to dissolve the crescent-shaped creatures; where it hit, ragged holes appeared. A terrible hissing, crackling sound came to my ears, even through the muffling mask I wore. "It works! It works!" Hendricks was crying over and over, hardly aware, in his excitement, that he was wearing a menore. "We're saved!" I put down three of the things in as many seconds. The central nucleus, in the thickest portion of the crescent, was always the last to go, and it seemed to explode in a little shower of crackling sparks. Hendricks accounted for four in the same length of time. "Keep back, sir!" he ordered in a sort of happy delirium. "Let them come to us! We'll get them as they come. And they'll come, all right! Look at them! Look at them! Quick, sir!"