"I'll pledge my reputation upon it," Bell said. "Hadn't you better telephone down to your electrician to come and see to those lights? I see the fuse in the meter is intact; it is only on the one circuit that they have gone." Van Sneck opened his eyes and stared languidly about him. In a clear, weak, yet wholly sensible voice he asked where he was, and then lapsed into slumber. A little later and he lay snug and still in bed. There was a look of the deepest pleasure in the eyes of Heritage. "I've saved him and he's saved me," he said. "But it was touch and go for both of us when that light failed. But for Bell I fancied that I should have fainted. And then it came to me that it was some trick, and my nerve returned." "Never to leave you again," Bell said. "It tried you high, and found you not wanting." "Heaven be praised," Heritage murmured. "But how was it done?" Bell's face was stern as he took the kitchen candlestick from the table and went in the direction of the dining-room. "Come with me, and I'll explain," he said, curtly. The dining-room was in pitchy darkness, for the lights there had been on the short circuit; indeed, the lights on the ground floor had all failed with the exception of the hall, which fortunately had been on another circuit. The fact had saved Van Sneck's life, for if Bell had not speedily used that one live wire the patient must have perished. Henson looked up from his sofa with a start and a smile. "I am afraid I must have been asleep," he said, languidly. "Liar," Bell thundered. "You have been plotting murder. And but for a mere accident the plot would have been successful. You have worked out the whole thing in your mind; you came here on purpose. You came here to stifle the light at the very moment when we were operating on Van Sneck. You thought that all the lights on the floor would be on the same circuit; you have been here before." "Are you mad?" Henson gasped. "When have I been here before--" "The night that you lured Van Sneck here by a forged letter and left him for dead." Henson gasped, his lips moved, but no words came from them. "You have a little knowledge of electricity," Bell went on. "And you saw your way pretty clear to spoil our operation to-night. You got that idea from yonder wall-plug, into which goes the plunger of the reading lamp on the cabinet yonder. At the critical moment all you had to do was to dip your fingers in water and press the tips of them against the live wire in the wall-plug. You did so, and immediately the wires fired all over the circuit and plunged us in darkness. But the hall light remained sound, and Van Sneck was saved. If it is any consolation to you, he will be as sensible as any of us to-morrow." "Hensen had risen to his feet, pale and trembling, He protested, but it was all in vain. Bell approached the china wall-plug and pointed to it.