Part 39 (2/2)

Gus and Jake had broken open the door of the stone tower. The soft purr of a motor told Penny that they had started draining the pool. She wondered what the men would do when they discovered that the tank contained a very live alligator.

”It ought to put a crimp in their work,” she chuckled. ”Mr. Kippenberg couldn't have chosen a more effective guard for his gold.”

But gradually as the pool drained lower and lower, it struck Penny as odd that the men did not notice the alligator. Belatedly, it occurred to her that the Kippenberg gardener had probably succeeded in getting rid of the monster since her visit to the garden earlier in the day.

”Something like that _would_ happen,” she thought. ”Oh, well, even so Jerry ought to get here with the police in ample time.”

Only the waning of the moon gave indication of how swiftly the night was pa.s.sing. Penny became alarmed as she observed how fast the pool emptied.

Jerry would not have as long as she had antic.i.p.ated. But surely, he would bring help before it was too late.

Presently, one of the men shut off the motor in the stone tower, saying with quiet jubilance:

”There, she's empty!”

He jumped down into the tank, and almost at once uttered a cry of discovery.

”Here it is, just as he said! The ring to the trap! Give us some help, Gus.”

With Aaron Dietz and the bewildered bridegroom watching from above, the two men raised the heavy block of cement. Penny drew closer for she did not wish to miss anything. She stood in the shadow of a tree scarcely fifteen yards from where the men worked.

”A stairway leads down into an underground vault!” Jake cried exultantly.

”We've found the hiding place of the gold.”

”Toss me your flashlight, Aaron,” called Gus. ”We'll soon have all of the treasure out of here.”

The next ten minutes brought a confused whirl of impressions. Penny's thoughts were in turmoil. Why didn't Jerry come with the police? As soon as the men carried the burden of gold to the boat they would discover Flora, bound and gagged. Then they would suspect that a trap had been laid. Oh, why didn't Jerry hurry?

Gus and Jake had descended into the underground vault. As the light reappeared, Penny was dumbfounded to see that the men were empty handed.

”Nothing down there,” Gus reported in disgust. ”Nothing!”

”Then we've been tricked!” Aaron Dietz turned furiously upon his prisoner. ”You'll pay for this!”

”I thought the gold was here,” answered Grant Atherwald.

”Lock him up in the vault and start the water running,” advised Jake harshly. ”It's a good way to be rid of him.”

The suggestion appealed to Aaron Dietz. At a nod from him, Atherwald was seized and dragged down into the pool. He was shoved into the vault, but before the two men could lower the heavy cement block into place, a signal from Dietz arrested their action.

”Wait!”

In her anxiety over Grant Atherwald, Penny had moved closer to the pool.

Without realizing that she was exposing herself, she stood so that her shadow fell clearly across the open s.p.a.ce. Before she comprehended her danger, Dietz hurled himself upon her, seizing her roughly by the arms.

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