The Duke waved his hand disparagingly. "Our secretary informs me," he went on, "that the subscription of Major Everett Anstruther is now due. It is suggested that he should produce this £56,000 worth of radium at our next meeting in payment thereof; although I believe that is something less than the value of membership of our Club." That is why, on April 4th last, Major Everett Anstruther climbed the wall at the back of Professor Blyth's house at Harlesden. His methods were those of the average burglar. He forced back the catch of one of the windows, drew up the sash, and stepped gently down from the window-sill into the room. He was in the Professor's laboratory, a one-storeyed building joined to the dwelling-house by a corridor. Anstruther turned on his portable electric light, and took his bearings. He was in an ordinary scientific laboratory, surrounded by induction coils, Crookes' tubes, balances, prismatic and optical instruments, and other and more complicated apparatus, the use of which he could not guess. He walked slowly round, observing every corner. Where was the radium? He had read up the subject, and had learnt of its power to penetrate almost any substance, and now he turned off his light, hoping to see its rays. There was nothing but absolute darkness. He resolved to explore further. He opened the door gently. In front of him was the passage leading to the house. At his left another door--wide open. He stopped before it in mute surprise and admiration. On a table in the middle of the room was a luminous mass. The wall behind was aglow with a dancing, scintillating light. The rest of the room was in darkness, save for the dim light cast by the glowing mass and the phosphorescent screen behind. It was the radium! How could the Professor leave it in so exposed a place? No doubt it was there that it had been exhibited to the scientists--but £56,000 worth left on a table for anyone to handle! It was absurd. Only a professor would have done it. But it wasn't for him to grumble at the peculiar methods of learned men, and with a cheerful heart Anstruther stepped lightly into the room. As he did so the door closed behind him with a click. The Major paused. "That's queer," he thought. "I didn't feel a draught, and I didn't touch the door." Luckily the laboratory was isolated from the rest of the house, so the slight noise would not have been heard. He waited for some minutes to reassure himself; then he stepped back to the door and gently turned the knob, without result. He pushed; pulled and pushed; lifted and pushed; pressed down and pushed; tried in every way he could think of, but the door would not open. He examined it carefully. Save for its knob its surface was absolutely plain. There was no keyhole or latch. "Trapped, by Jove!" Anstruther exclaimed under his breath; and as his unpleasant situation dawned upon him he felt more uncomfortable than he had ever done in his life before. In fact, he felt physically ill.