"Did he?" went on Anderson inexorably.
Dale stared at him, dully--the breaking point had come. Another question--another--and she would no longer be able to control herself. She would sob out the truth hysterically--that Brooks, the gardener, was Jack Bailey, the missing cashier--that the scrap of blue-print hidden in the bosom of her dress might unravel the secret of the Hidden Room--that-But just as she felt herself, sucked of strength, beginning to slide toward a black, tingling pit of merciful oblivion, Miss Cornelia provided a diversion.
"What's that?" she said in a startled voice.
The detective turned away from his quarry for an instant.
"What's what?"
"I heard something," averred Miss Cornelia, staring toward the French windows.
All eyes followed the direction of her stare. There was an instant of silence.
Then, suddenly, traveling swiftly from right to left across the shades of the French windows, there appeared a glowing circle of brilliant white light. Inside the circle was a black, distorted shadow--a shadow like the shadow of a gigantic black Bat! It was there--then a second later, it was gone!
"Oh, my God!" wailed Lizzie from her corner. "It's the Bat--that's his sign!"
Jack Bailey made a dash for the terrace door. But Miss Cornelia halted him peremptorily.
"Wait, Brooks!" She turned to the detective. "Mr. Anderson, you are familiar with the sign of the Bat. Did that look like it?"
The detective seemed both puzzled and disturbed. "Well, it looked like the shadow of a bat. I'll say that for it," he said finally.
On the heels of his words the front door bell began to ring. All turned in the direction of the hall.
"I'll answer that!" said Jack Bailey eagerly.
Miss Cornelia gave him the key to the front door.
"Don't admit anyone till you know who it is," she said. Bailey nodded and disappeared into the hall. The others waited tensely. Miss Cornelia's hand crept toward the revolver lying on the table where Anderson had put it down.
There was the click of an opening door, the noise of a little scuffle--then men's voices raised in an angry dispute. "What do I know about a flashlight?" cried an irritated voice. "I haven't got a pocket-flash--take your hands off me!" Bailey's voice answered the other voice, grim, threatening. The scuffle resumed.
Then Doctor Wells burst suddenly into the room, closely followed by Bailey. The Doctor's tie was askew--he looked ruffled and enraged. Bailey followed him vigilantly, seeming not quite sure whether to allow him to enter or not.
"My dear Miss Van Gorder," began the Doctor in tones of high dudgeon, "won't you instruct your servants that even if I do make a late call, I am not to be received with violence?"