CHAPTER XIII MARPLOT Once sheltered by the privacy of her bedchamber and seated before the little white-enamel desk with its chintz-covered fittings that suited so well the simple, cheerful scheme of decoration, the girl lingered long, an idle pencil caught between fingers infirm of purpose. Her gaze was fixed as if hypnotised to the blank white face of the bit of cardboard that lay before her on the blotting-pad, her thoughts far astray in a dark jungle of horror, doubts, suspicions, fears. Immediately after shutting herself in she had gone straight to this desk, possessed by the notion that there was a message requiring to be written upon the card, one self-exculpatory sentence which had framed itself in her mind as she sped down the corridor from that remarkable meeting in Mrs. Gosnold's rooms. "I have not told you everything--but I am innocent," thus ran the words which she felt were demanded of her and a legitimate privilege, her duty to herself in sheer self-preservation. And as they wrote themselves down before her mental vision she saw two heavy strokes of the pen underlining "everything," and her own true name, Sarah Manvers, following in the place of the signature--no more "Sara Manwaring," Mrs. Gosnold's explicit commands to the contrary notwithstanding. But that had been an impulse, only natural in the first shock of horror inevitably attending the disclosure of the robbery, to clear herself; or, rather, to reaffirm her innocence. For with second thought had come the consideration: Was she not already cleared, was her innocence not already established? She was prepared to believe that Mrs. Gosnold knew everything. That extraordinary woman! What had she not known, indeed? Mark how cunningly she had drawn from Sally the admission that she had been up and about the house and grounds long after she had gone to her bedchamber for the night--at the very time, most probably, when the robbery was being done! And that had been by way of preface to the pledge she had made Sally of her protection before startling confession from the girl--a pledge not only given in advance, but by implication at least renewed when the truth was out. If she had believed Sally guilty, or party to the crime, or even in possession of guilty knowledge of it, would she have made that generous promise? She was kind of heart, was Mrs. Gosnold, but she was nobody's fool; if she had not been well satisfied in her own mind as to the thief she would never have so committed herself to Sally, for she was no one to give her word lightly or, as she herself had said, to bait a trap with fair words and flattery. In vain Sally searched her memory for anything to warrant an assumption that her mistress had been in any way ignorant of that black business of the small hours. She had neither denied such knowledge nor asserted it, but had simply permitted Sally to leave out of her account all reference to the overnight adventure.