"After this Mr. Topsparkle was a frequent visitor to my son's sitting-room, but as he never saw my granddaughter alone the most careful father would scarcely conceive the possibility of danger. "So insidious were the approaches of the seducer, so completely was the father hoodwinked, that the first indication of danger was the fall of a thunderbolt. One evening in late autumn, between sunset and darkness, Margharita disappeared. No one saw her leave the house, but she was gone; and as she never went out alone, but was always escorted by an old servant who had been her mother's nurse as well as her own, her absence created immediate alarm. "My son was like a man distracted. He searched every public resort, went over the whole city on foot or in a gondola, visited his few friends, hunted every likely and unlikely place for some trace of his lost daughter, but found none. He came to me at ten o'clock in my laboratory, to ask my advice. He was half dead with fatigue, broken down with the agony of apprehension. "The greatness of this calamity startled me into an awakened interest in the outer life around me. My sympathy with my son in his distress roused my reason to new action. "'It must mean one of three things,' I told him: 'accident, suicide, or flight with a lover.' "'What accident is possible? She could not have fallen out of a window or into the canal without our knowing all about it. Suicide is impossible. Lover she had none.' "'Are you sure of that?' "'She was never out of my sight. We have had no visitors--except the Englishman who came to hear her singing.' "'Then the Englishman is the lover,' I said; and the thought flashed upon me with the force of conviction, 'it is the Englishman who has carried her off.' "My unhappy son sprang to his feet in a paroxysm of despair. "'It was I that brought him to her room. I was proud of his admiration of her genius,' he cried; 'I was fooled by his patronage, his art, his liberality, his specious tongue. But her lover--no, that is impossible. There was no opportunity for love-making. I was always there. The English signor was distant in his politeness; he respected her station and his own. He could not be her lover; I say it is impossible.' "'Anything is possible to the practised seducer. It is to that man you must look for your daughter's fate.' "'I will go to his house this instant,' said Filippo. "'I will go with you.' And then recalling what I had heard at the coffee-house, I said, 'There are two houses which we have to search--the palace on the Canal Reggio, and that secret apartment which I have only heard of from people who knew not the locality. But if there is such an apartment, the scene of secret orgies, hidden infamies, it is for us to find it.'