“A little invention of my own for measuring foot-prints,” Quest explained.  “Not much use here, I am afraid.”

“What do you think of the affair so far, Mr. Quest?” the Professor asked eagerly.

The criminologist shook his head.

“Incomprehensible,” he confessed.  “Can you think, by-the-bye, of any other motive for the theft besides scientific jealousy?”

“There could be no other,” the Professor declared sadly, “and it is, alas! too prevalent.  I have had to suffer from it all my life.”

Quest stood over the box for a moment or two and looked once more out of the window.  Presently Lenora returned.  She carried in her hand a small object, which she brought silently to Quest.  He glanced at it in perplexity.  The Professor peered over his shoulder.

“It is the little finger!” he cried,—­“the little finger of my ape!”

Quest held it away from him critically.

“From which hand?” he asked.

“The right hand.”

Quest examined the fastenings of the window before which he had paused during his previous examination.  He turned away with a shrug of the shoulders.

“See you later, Mr. Ashleigh,” he concluded laconically.  “Nothing more to be done at present.”

The Professor followed him to the door.

“Mr. Quest,” he said, his voice broken with emotion, “it is the work of my lifetime of which I am being robbed.  You will use your best efforts, you will spare no expense?  I am rich.  Your fee you shall name yourself.”

“I shall do my best,” Quest promised, “to find the skeleton.  Come, Lenora.  Good morning, gentlemen!”

* * * * *

With his new assistant, Quest walked slowly from the museum and turned towards his home.

“Make anything of this, Lenora?” he asked her.

She smiled.

“Of course not,” she answered.  “It looks as though the skeleton had been taken away through that window.”

Quest nodded.

“Marvellous!” he murmured.

“You are making fun of me,” she protested.

“Not I!  But you see, my young friend, the point is this.  Who in their senses would want to steal an anthropoid skeleton except a scientific man, and if a scientific man stole it out of sheer jealousy, why in thunder couldn’t he be content with just mutilating it, which would have destroyed its value just as well—­What’s that?”

He stopped short.  A newsboy thrust the paper at them.  Quest glanced at the headlines.  Lenora clutched at his arm.  Together they read in great black type—­

Escape of convicted prisoner!

Macdougal, on his way to prison,
grapples with Sheriff and jumps
from train!  Still at large
though searched for by
Posse of police