"Surely you wouldn't do that," protested Nick, who up to this time had been watching the effort of the two airmen with quiet amusement. "If you blow up the safe you might set fire to the castle and destroy all the treasures you have won." "Oh, hold your tongue!" advised Strut. Dragging two smouldering logs from the grate, he shoved them under the safe. Then, unscrewing the end of his flying stick, he sprinkled a fine, black powder that smelled and looked like gun powder, over the logs. Lighting a twisted paper, he stuck it beneath the logs and jumped back, waiting impatiently for the safe to fly apart. Nick Chopper waited not a moment longer. Darting into the dressing room he hastily filled a pitcher with water. But before he could return, an ear-splitting explosion rocked the castle and flung him and the pitcher through the doorway of the sitting room. Without stopping to recover his breath, the Tin Woodman jumped up and hurried across the room. The two airmen, with blackened clothes and faces, stared dazedly at the spot where the safe had been. _Where it had been_--because it was no longer there! Not a sign, emerald or single splinter of it! There was no hole in the ceiling, so it could not have blown up; there was no hole in the floor, so it could not have blown down. The windows were unbroken, the walls, intact. Only the two logs, smoking sullenly on Ozma's priceless rug, remained of the Airlander's bonfire--unless we count the expression on Strut's face, which simply blazed with wrath, bafflement and unadulterated fury. CHAPTER 19 The Travellers Return! "I told you not to do that," said Nick, running over to Strut and the Swordsmith. "I warned you! Now see what you've done!" "But where is it? Where did it go? Where did it BLOW?" screamed the Airlander, his electric hair standing more on end than ever and crackling like summer lightning. "Ask Ozma! Ask the Wizard!" suggested Nick, folding his arms and surveying the two quite calmly. "But if you take my advice, you'll hustle right out of this castle before the same thing happens to YOU!" "Who asked for your advice?" cried Strut, streaking over to the window to see whether the safe had blown into the garden, though how it could have done so without knocking a hole in the wall or ceiling, he could neither imagine nor understand. Drawing aside the curtain he gave a great gasp. Nick, who had hurried after him, uttered a loud shout of joy. "See! I told you!" cried Nick, and unhooking his oil can the Tin Woodman let four drops of oil slide down his neck. "I told you!" Strut made no reply. He just hung on to the curtain as if he were drowning and the flimsy portiere, a life preserver. "See!" shouted Nick again.