"Very well. Arthur Sloane is prostrated, can't be interviewed. He can't be interviewed, for the simple reason that he's afraid he'll tell what he knows. Why is he afraid of that? Because he knows too much, for his own comfort, and too much for his daughter's comfort. How does he know it? Because he saw enough night before last to leave him sure of the murderer's identity.
"He was the man who turned on the light, showing Webster and Judge Wilton bending over Mildred's body. It occurred at a time when usually he is in his first sound sleep—from bromides. Something must have happened to awake him, an outcry, something. And yet, he says he didn't see them—Wilton and Webster."
"By gravy!" exclaimed the sheriff, awe-struck.
"Either," she continued, "Arthur Sloane saw the murder done, or he looked out in time to see who the murderer was. The facts substantiate that. They are corroborated by his subsequent behaviour. Immediately after the murder he was in a condition that couldn't be explained by the mere fact that he's a sufferer from chronic nervousness. When Hastings asked him to take a handkerchief, he would have fallen to the ground but for the judge's help. He couldn't hold an electric torch. And, ever since, he's been in bed, afraid to talk. Why, he even refused to talk to Hastings, the man he's retained for the family's protection!"
"He did, did he! How do you know that, Mrs. Brace?"
"Isn't it enough that I know it—or advance it as a theory?"
"Did—I thought, possibly, Jarvis, the valet, told you."
She ignored that.
"Now, as to the daughter of the house. There was only one possible reason for Lucille Sloane's hiring Hastings: she was afraid somebody in the house, Webster, of course, would be arrested. Being in love with him, she never would have suspected him unless there had been concrete, undeniable evidence of his guilt. Do you grasp that reasoning?"
"Sure, I do!" Mr. Crown condemned himself. "What I'm wondering is why I didn't see it long ago."