“Celia let him in; who let him out? What really happened?” she was thinking. “How, when and why did I begin to build up my castle of falsehood?” She stopped dead half way up the stairs; it was the little window, she remembered, which had first convinced her it was Philip just because she was sure Celia could not have done that. In her revulsion of feeling she now absolved Philip afresh; who broke the window then? Suddenly without seeking for it she remembered every word of her conversation with Birts about that window. How blind she had been to its real significance! The breakage had not been discovered till two o’clock on the day after the murder. It might, then, have been done any time between after dinner on the night of the murder and two o’clock next day; it might have been done, the thought came insistently, on the morning after the murder. It might, yes, but why should it have been? No answer suggested itself, but it was with quickened interest in the sudden opening up of a new avenue of thought that she continued her way slowly upstairs. CHAPTER XII Out of the Darkness During luncheon Evelyn sat absorbed in her own thoughts, and spoke little and then at random. Celia, her only companion at the meal, was naturally full of questions; how did Evelyn know John had not done it? Why had she left her so suddenly? And the like, to all of which Evelyn returned evasive answers. She could not shake herself free from the baffling problems of the tragedy, no matter how often or how sincerely she resolved to leave them alone. She had been hopelessly, grievously wrong, but how and why? What had made her go wrong? On what false basis had she reared her crazy edifices? “Some one,” her mind kept repeating to her, “barred that window; John couldn’t do it himself; you have heard and you believe Celia’s story, you have followed Philip’s trail and it has led you to an absurdity. Who remains?” Then her mind ran away with her to the new fact which had just penetrated her consciousness, that there was a large margin of time inside which the little window might have been broken; it was probable of course that it had been done soon after the murder, but it was odd, if that was so, that it had not been discovered many hours earlier than it was. Supposing it had been done the morning after, what could she make of that? Who could have done it, and what was the reason why it was done? It was so easy to make suppositions, so easy to ask questions, but she seemed to be led into a blank wall when she tried to answer them.