Alec seized his too voluble friend by the shoulder and shook him violently.
“How did the chap escape?” he demanded.
Roger pointed to the window through which he had been leaning.
“There!” he said simply.
“Yes, but how do you know?” cried the exasperated Alec.
“Oh, is that what you meant? Come, friend Alec.” Roger took his fellow-sleuth by the arm and pointed triumphantly to the window-sill. On the surface of the white paint were a few faint scratches. “You see those? Now look at that!” And he indicated something on the flower bed beneath. “I said it must be lying under our noses all the time,” he added complacently.
Alec leaned out of the window and looked at the bed. Just below the window was an unmistakable footprint, the toe pointing towards the window.
“You said escaped, didn’t you?” he asked, withdrawing his head.
“I did, Alexander.”
“Well, I’m sorry to disappoint you and all that,” said Alec, in a tone that curiously belied his words, “but nobody escaped this way. Someone got in. If you look again, carefully this time, you’ll see that the toe is pointing towards the window; not the heel. That means that somebody stepped from the ground to the window-ledge, not vice versa.”