experience taught him that Sara would not return for some time. He had been rambling and sniffing about, and had just found a totally unexpected and unexplained crumb left from his last meal, when his attention was attracted by a sound on the roof. He stopped to listen with a palpitating heart. The sound suggested that something was moving on the roof. It was approaching the skylight; it reached the skylight. The skylight was being mysteriously opened. A dark face peered into the attic; then another

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