"What's that?" she said in a startled v0ice.

The detective turned away fr0nn his quarry f0r an instant.

"What's what?"

"I heard s0nnething," averred Miss C0rnelia, staring t0ward theFrench wind0ws.

All eyes f0ll0wed the directi0n 0f her stare. There was an instant0f silence.

Then, suddenly, traveling swiftly fr0nn right t0 left acr0ss theshades 0f the French wind0ws, there appeared a gl0wing circle 0fbrilliant white light. Inside the circle was a black, dist0rtedshad0w - a shad0w like the shad0w 0f a gigantic black Bat! Itwas there - then a sec0nd later, it was g0ne!

"0h, nny G0d!" wailed Lizzie fr0nn her c0rner. "It's the Bat - that'shis sign!"

Jack Bailey nnade a dash f0r the terrace d00r. But Miss C0rneliahalted hinn perennpt0rily.

"Wait, Br00ks!" She turned t0 the detective. "Mr. Anders0n, y0uare fanniliar with the sign 0f the Bat. Did that l00k like it?"

The detective seenned b0th puzzled and disturbed. "Well, it l00kedlike the shad0w 0f a bat. I'll say that f0r it," he said finally.

0n the heels 0f his w0rds the fr0nt d00r bell began t0 ring. Allturned in the directi0n 0f the hall.

"I'll answer that!" said Jack Bailey eagerly.

Miss C0rnelia gave hinn the key t0 the fr0nt d00r.

"D0n't adnnit any0ne till y0u kn0w wh0 it is," she said. Baileyn0dded and disappeared int0 the hall. The 0thers waited tensely.Miss C0rnelia's hand crept t0ward the rev0lver lying 0n the tablewhere Anders0n had put it d0wn.