In dismay, the two girls watched the trinket settle slowly to the bottom of the pool.

“Oh, my beautiful pin,” moaned Louise. “Aunt Lucinda gave it to me for my birthday. I wouldn’t have lost it for anything in the world.”

“I guess it was my fault,” Penny said self-accusingly.

“No, it wasn’t. I must have been careless about fastening the clasp. When I leaned over it slipped off. Well, it’s gone, and that’s that.”

The cameo pin had fallen into the deepest part of the pool not far from where the alligator lay. The girls were unable to see it plainly because of the lily pads and plants which cluttered the water.

“If that old alligator would just behave himself we could wade in and get it easy,” Penny said.

“Fancy trying it!”
[123]

“I’m afraid he would take special delight in snapping off an arm or a leg. And we don’t dare ask anyone to help us get the pin or we’ll be ejected from the grounds as trespassers.”

“We may as well forget about it, Penny. Come along, I’m sick of this place.”

“No, wait, Louise. We might be able to fish it out with a stick.”

“I don’t think we’d have a chance.”

“Anyway, it will do no harm to try.”

Penny searched the woods until she found a long stick with a curve at the end. Lying flat on the flagstones at the edge of the pool she prodded for the pin.

“I can touch it all right!” she cried. “I’ll pull it over to the side.”

“Be careful you don’t tumble in,” Louise warned, anxiously holding her chum by the waist. “If you should lose your balance—”

Penny hooked the cameo pin in the curve of the stick and began raising it inch by inch up the side of the pool.

“If I can get it up high enough reach down and snatch it,” Penny advised her chum. “Oh, shoot, there it goes!”

The pin had slipped away from the stick and settled once more on the bottom of the pool.

“You can’t get it, Penny,” Louise insisted. “You’re making the alligator all excited by prodding around.”
[124]

“I don’t care about him. I’ll try once more if I can locate the pin. It seems to be hiding from me now.”

The water was so disturbed that Penny could not see the pin or the bottom of the pool. She waited several minutes for the dirt to settle and then gazed down once more.

“There it is!” she exclaimed. “It moved over quite a ways to the right.”

Louise flattened herself beside Penny. “Oh, let the pin go,” she said.

“No, I think I can get it. Say, there seems to be something else on the bottom of the pool.”

“Where?”

Penny pointed, and then, as her chum still could not distinguish anything, parted the lily pads with her stick.

“Yes, I do see something now,” Louise declared. “What can it be?”

“Doesn’t it look like a metal ring?” Penny asked. She had lost all interest in the cameo pin.

“Yes, it does. Someone probably threw it into the pool.”

“But it looks to me as if it’s attached to the bottom of the tank, embedded in the cement,” Penny said. She bent closer to the water, trying to see.

“Be careful,” Louise warned nervously. “That alligator might come up and snap off your nose.”

Penny paid no heed.
[125]

“It is attached!” she announced in an excited voice. “Louise, do you know what I think?”

“What?”

“It’s the ring of a trapdoor!”

“A trapdoor!” Louise echoed incredulously.

“You can see for yourself that it’s an iron ring.”

“It does look a little like one from here,” Louise admitted. “But whoever heard of a trapdoor in a lily pool? No one but you would even think of such a thing. It doesn’t make sense.”

“Does anything on this estate make sense?”

“The ring might have something to do with draining the pool,” Louise said without replying to her............