"Mercy!" gasped the Italian, and putting out his hand he grasped a long red switch marked 'Danger' and pulled it over. Instantly all the lights in the power house went dim, and the great whirling wheels slowed down and stopped. Only the light of day illuminated the power house. Ela, standing on the controlling platform, wiped his perspiring face with the back of a hand which was shaking as though with ague. "I wonder if I was in time?" he muttered. The big machinery hall was now alive with detectives. "Take charge of every man," Ela ordered; "see that nobody touches any of these switches. Arrest stokers and keep them apart. Now you," he said, addressing the foreman in Italian, "you seem a decent fellow, and I am going to give you a chance of earning not only your freedom, but a substantial reward. I am a police officer and I have come to make an inspection of this house. You spoke of the lower rooms--do you know the way there?" The man hesitated. "The lift cannot work, signor," he said, with a shrug of his shoulders, "now that the electric current is stopped." "Is there no other way?" Again the man hesitated. "There are stairs, signor," he stammered after a while, then continued rapidly: "If this is a crime and Signor Moole is an anarchist, I know nothing of it, I swear to you by the Virgin. I am an honest man from Padua, and I have no knowledge of such things as your Excellency speaks about." Ela nodded. "I am willing to believe that," he said in a milder tone. "Now, my friend, you shall undo a great deal of mischief that has been done by showing me the way to the underground rooms." "I am at your service," said the man helplessly. "I call all men to witness that I have done my best to carry out the instructions which the padrone has given me." He led the way out of the power house through a door which led to a large stretch of private garden behind the main building, across a well-kept lawn to an area basement which ran the whole length of the house. In this, at the far end, was a door, and the man opened it with a key upon a bunch which he took from his pocket. They had to pass through two more doors before they came to the spiral staircase which led down into the gloomy depths beneath the Secret House. To Ela's surprise they were illuminated and he feared that against his orders the dynamo had been restarted, but the man reassured him. "They are from the storage batteries," he said. "There is sufficient to afford light all over the house, but not enough to give power." The steps seemed never ending. Ela counted eighty-seven before at last they came to a landing from which one door opened. The detective noticed that the man employed the same method of entering here as he himself had done. A bodkin slipped into an almost invisible hole produced the mechanical unsealing of this doorway.