He was getting confused, obfuscated: he would search for the keys in the morning: perhaps, after all, he had left them in the dressing-room.
Throughout the remaining hours of that awful night, he lay pondering the momentous question, at one moment burning with fever, at another icy cold.

The dawn broke, the sun rose, the room grew hot; and the heat gave him an idea.

As the clock struck six, he rose, put on his boating flannels, and, with his bath towel over his arm, opened the bedroom door.

He had actually forgotten the missing keys! Such lapses are common to the criminal.
Miriam was a light sleeper--as her awaking at the noise of the falling chair had proved--she became conscious of his presence and she opened her eyes.
"Oh, what is it, Percy ?" she asked, petulantly and a little nervously.
"I'm going down to the lake for a swim," he said; "it's precious hot this morning.

I left my white shoes in the room." "No, you didn't," she said, impatiently.