"I'll just fly down and see what's up," quavered Roger, and in spite of the loud shouts and threats of Ato on the _Crescent Moon_, the Read Bird spread his wings and coasted slowly and bravely into the immense air shaft. Nikobo, now as alarmed as the ship's cook, began swimming frantically round the edge of the misty chasm, letting out piercing blasts that sounded like nothing so much as a ferry boat whistle. Tandy himself felt uneasy and frightened and Ato, unable to bear the suspense any longer, climbed over the side and came swimming out to join them. After an endless fifteen minutes, during which dreadful fear and premonition gripped the watchers, the head of the Read Bird popped mournfully into view. "Is he all right? Where's Sammy? What in soup's he doing? What'd you find out?" gasped Ato, reaching out to clutch Roger by the wing. Roger, limp and bedraggled, with all the stiffness out of his feathers, said nothing for a whole minute. Then, beating his wings together, he began to scream out hoarsely, "The Captain's caught! The Collector's collected. They have Master Salt forty fathom below. They've got him shut up, I mean down at the bottom of the sea like a gold fish in a bowl, only he's in a big bowl of air. They're poking little fish and crabs through a trap door in the air shaft and I cannot break or even make a dent in the transparent slide they've shot across the air hole to shut him off from us. And oh, my bill and feathers! Every time they open the trap door to shove things in to him, water rushes into the vacuum. He's standing in water to his knees now and unless we can break a hole in that lid the Captain's done for--done for, do you hear?" "They?" asked Tandy while Nikobo's eyes almost popped out of her head, "Who do you mean?" "Oh, oh, don't ASK me!" choked the poor Read Bird. "They're not fish and they're not men. They're about the size of Tandy, here, sort of stiff and jellied and perfectly transparent. On a shell hanging outside of one of their caves it said 'Seeweegia.'" "Seeweegia!" moaned Ato, clutching his head in both hands. "Let me see! Let me see! What's to be done, boys? Now quick! What's to be done?" "Have Roger fetch the saw we used on the whale's horn," gurgled Nikobo. "And I'll climb down and saw a hole in that slide," cried Tandy eagerly. "No, _I'll_ climb down," said Ato firmly. "I've known Sammy the longest and if he's going to come to a watery end I might as well end with him." Leaving the two arguing, Roger flashed back to the ship, returning in almost no time with the scintillating and powerful saw. Tandy had meanwhile convinced Ato that he could climb down the rope faster, being so much lighter, and now, with tears in their eyes, Nikobo and the ship's cook saw Tandy and Roger disappear into the air shaft.