"It was he, I tell you!" he was exclaiming. "It couldn't have been anyone or anything else but the Invisible Master--the package vanished right before my eyes!" "Who's the youngster?" Carton asked of one of the reporters beside him. "Harkness, the teller," said the other. "He's claiming that a package of fifty one-thousand dollar bills vanished in front of his eyes, and it looks as though he's going to have a hard time convincing his bosses," added the other cynically. Grantham was calming the excited young teller. "Let's just hear all about it," he told him. "We know that the thing's unprecedented, and no one thinks you took the money." Harkness made an effort to appear calm. "It was just half an hour ago," he said. "I was arranging some entries in my sheets and the package was lying with some others beside me, just inside the grille's opening. It was really in reach from outside, of course, but there was no danger because everyone knows how impossible it is to snatch money in a bank and escape with it. I thought I heard someone step up to my window and looked up, but there was no one there. Then in a minute it happened--the whole front of the grille and counter seemed to vanish for a second and then reappear. But when they reappeared the package of thousand-dollar bills was gone! I could only stare, stupefied, for no one had been at the window, and then suddenly I remembered about the Invisible Master and gave a shout. The guards came running--but there was no one there by then. It was the Invisible Master--and he had gone! And it was he--I tell you it must have been!" Harkness' calm broke down at the end of his story, but Grantham encouraged him with a few words and then turned to Wade. "The boy's telling the truth, Wade," he said simply. "It was the Invisible Master--and he's given us the first sample of what his being loose in this city means!" The officials and reporters were silent, Wade thoughtful. "Would it be possible for him to make the whole front of the counter disappear for an instant like that?" he asked Grantham. The physicist nodded. "Quite possible. You see, the projector when attached to the body, projects a force for a radius of a few feet around the body and makes all in that radius invisible as well as the person wearing it. Thus when the Invisible Master stepped close up to the window, it and everything in the projector's radius became invisible for a second, and in that second he needed only to grasp the package of bills and then step quickly back and walk out." "It's a tough problem," Wade admitted. He and Grantham had stepped aside from the group, who were now sharply questioning Harkness, and Carton had followed them. "But how are you going to deal with it?" Grantham demanded. "For all we know, Wade, the Invisible Master may be even now going through bank after bank. It's not a question of doing anything about this robbery so much as of preventing others."