“I get ‘r’, ‘d’, and ‘b’ a lot,” he signed, turning the receiver over to Sparks again. “They are in rotation--‘r’, ‘d’, ‘b’--and sometimes there follows another ‘d’. There are letters missing between them, excepting between the ‘b’ and the first ‘d’.” “No ‘help’ stuff, eh?” queried Sparks. “Nor any ‘_Colodia_’,” snorted Belding. But he sat and watched the radio chief give his full attention to the mystery, and after a minute or two saw that the man was spelling something out carefully on the pad of scratch-paper under his hand. Belding peered over his shoulder and saw Sparks set down these letters as he heard them in the sound waves: R DB R DB R R DB D RE B D R D RD R DB RE I Sparks pulled off the harness and swung about to look at George Belding. “Is that about what you heard?” he demanded. “Yes, sir. At least, in part.” “Well, hang it all!” cried Sparks. “That’s a still newer combination. It’s neither ‘_Colodia_’ nor ‘help.’ I tell you it beats me, George.” When Belding left the wireless room he took with him the piece of paper on which Sparks had written. The letters in combination seemed to mean nothing; but he showed them to Whistler and Al Torrance when he found those two chums together. “Looks like one of those puzzles they have on the back page of the papers at home,” said Al. “You know: The ones you are supposed to fill in with other letters to make ’em read the same up and down and across.” “This is no acrostic,” said Belding firmly. But Whistler stared steadily at the paper for some minutes without saying a word. Only his lips slowly puckered, and Al nudged him to break off the thoughtful whistle which he knew his chum was about to vent. “Huh? Oh! All right,” murmured Morgan, accepting Al’s admonition. “What do you see?” asked Belding. “I see that it is the same word each time, of course,” replied Whistler. “But I don’t believe my eyes.” “What’s that?” demanded the other two boys. “If the ghost of the air,” said Whistler gravely, “did not spell out the name of this destroyer this afternoon, it certainly did try to put over the name of another ship.” “Wow!” exclaimed Al. “Tell us.” “What ship do you mean?” asked Belding, scowling thoughtfully at the paper. Quickly Whistler covered the letters on the sheet as, with his own pencil, he filled in the gaps between them. When he flashed the sheet before the eyes of his two friends each of the lines of letters made the same word. And that word was: REDBIRD “My goodness! You have gone crazy, Phil Morgan!” almost shouted Belding. “Cracky! that’s the ship your sisters and Belding’s folks are aboard, you know,” gasped Torry. “Why, Whistler, I believe with George that you _are_ crazy!” “All I see,” said Morgan, quite unruffled, “is that George brought us some letters that, very easily and sensibly, make the name of his father’s ship now bound for Bahia.” “Cracky!” exclaimed Al again.