Lady Audley's eyes were still fixed upon the burning coals in the wide grate. She spoke as if she had been discussing a subject that she had often heard discussed before. She spoke as if her mind had almost wandered away from the thought of her husband's nephew to the wider question of madness in the abstract.
"Why should he not be mad?" resumed my lady. "People are insane for years and years before their insanity is found out. They know that they are mad, but they know how to keep their secret; and, perhaps, they may sometimes keep it till they die. Sometimes a paroxysm seizes them, and in an evil hour they betray themselves. They commit a crime, perhaps. The horrible temptation of opportunity assails them; the knife is in their hand, and the unconscious victim by their side. They may conquer the restless demon and go away and die innocent of any violent deed; but they may yield to the horrible temptation--the frightful, passionate, hungry craving for violence and horror. They sometimes yield and are lost."
Lady Audley's voice rose as she argued this dreadful question, The hysterical excitement from which she had only just recovered had left its effects upon her, but she controlled herself, and her tone grew calmer as she resumed: "Robert Audley is mad," she said, decisively. "What is one of the strangest diagnostics of madness--what is the first appalling sign of mental aberration? The mind becomes stationary; the brain stagnates; the even current of reflection is interrupted; the thinking power of the brain resolves itself into a monotone. As the waters of a tideless pool putrefy by reason of their stagnation, the mind becomes turbid and corrupt through lack of action; and the perpetual reflection upon one subject resolves itself into monomania. Robert Audley is a monomaniac. The disappearance of his friend, George Talboys, grieved and bewildered him. He dwelt upon this one idea until he lost the power of thinking of anything else. The one idea looked at perpetually became distorted to his mental vision. Repeat the commonest word in the English language twenty times, and before the twentieth repetition you will have begun to wonder whether the word which you repeat is really the word you mean to utter. Robert Audley has thought of his friend's disappearance until the one idea has done its fatal and unhealthy work. He looks at a common event with a vision that is diseased, and he distorts it into a gloomy horror engendered of his own monomania. If you do not want to make me as mad as he is, you must never let me see him again. He declared to-night that George Talboys was murdered in this place, and that he will root up every tree in the garden, and pull down every brick in the house in search for--"