Sure enough, there was the sign of the hand.  He hastily got out of the car and hurried up the street.  All this time the chauffeur was keeping Jennings busy over the telephone with some trumped-up story.

As the master criminal came in by the ladder through the open window, Dan was on guard, listening down the hallway.  A signal from Dan, and Clutching Hand slid back of the portieres.  Jennings was returning.

“I’ve finished these windows,” announced Dan as the butler reappeared.  “Now, I’ll clean the hall windows.”

Jennings followed like a shadow, taking the bucket.

No sooner had they gone than Clutching Hand stealthily came from behind the portieres.

One of the maids was sweeping in the hall as Dan went toward the window, about to wash it.

“I wonder whether I locked these windows?” muttered Jennings, pausing in the hallway.  “I guess I’d better make sure.”

He had taken only a step toward the library again, when Dan watchfully caught sight of him.  It would never do to have Jennings snooping around there now.  Quick action was necessary.  Dan knocked over a costly Sevres vase.

“There—­clumsy—­see what you’ve done!” berated Jennings, starting to pick up the pieces.

Dan had acted his part well and promptly.  In the library, Clutching Hand was busily engaged at that moment beside the secret panel searching for the spring that released it.  He ran his finger along the woodwork, pausing here and there without succeeding.

“Confound it!” he muttered, searching feverishly.

. . . . . . . .

Kennedy, having made the arrangements with the telephone company by which he had a clear wire from the Dodge house to his laboratory, had rejoined me there and was putting on the finishing touches to his installation of the vocaphone.

Every now and then he would switch it on, and we would listen in as he demonstrated the wonderful little instrument to me.  He had heard the window cleaner and Jennings, but thought nothing of it at the time.

Once, however, Craig paused and I saw him listening more intently than usual.

“They’ve gone out,” he muttered, “but surely there is someone in the Dodge library.”

I listened; too.  The thing was so sensitive that even a whisper could be magnified and I certainly did hear something.

Kennedy frowned.  What was that scratching noise?  Could it be Jennings?  Perhaps it was Rusty.

Just then we could distinguish a sound as though someone had moved about.

“No—­that’s not Jennings,” cried Craig.  “He went out.”

He looked at me a moment.  The same stealthy noise was repeated.

“It’s the Clutching Hand!” he exclaimed excitedly.

. . . . . . . .

A moment later, Dan hurried into the Dodge library.

“For heaven’s sake, Chief, hurry!” he whispered hoarsely.  “The falsers must have fallen down.  The girl herself is coming!”