“By inspecting the sash. I had a good look at it from the inside and out. Apparently it hadn’t been opened for some time before last night, and the marks of the knife which was used to force it were very distinct in the sash in consequence. But the marks were broader and more distinct at the top of the sash inside than at the bottom. Therefore the knife was inserted at the top, and that could be done only by a man inside the house.”
“But why was the window forced if the man was inside?”
“In order to mislead us.”
“But the footprints led up to the window.”
“No,” said Crewe. “They led away from it.”
“Surely you are mistaken,” said Marsland. “I don’t like trying to put you right on a matter of this kind, but the marks of the boots were so distinct; they all pointed the one way—towards the window.”
“Look behind you, at our own footprints in the sand,” said Crewe.
They had left the rocks behind them some time previously and for five minutes had been walking on a strip of sand which skirted the cliff road—now level with the sea—and broadened into a beach nearer the village. Crewe pointed to the clear imprint of their footsteps in the firm wet sand behind them.
“We’ll try a little experiment,” he said. “Let us walk backwards for a few yards over the ground we have just covered.”
He commenced to do so, and Marsland wonderingly followed suit. After covering about twenty yards in this fashion Crewe stopped.