With a sneer Dora turned and led the way down-stairs again.

“They’ll find his body when they have to clean the tank again,” she exclaimed.

At Brent Rock, during the absence of Locke, Eva had donned her street clothes, since it was nearing the hour of eight when she and Locke were due to be at the inventor’s workshop to render the restitution.  She went down-stairs and asked the butler about Locke.  But the man replied that Mr. Locke had not yet returned.

Eva was very uneasy by this time, and, thinking to save time, was about to go down to the Graveyard of Genius to get the models of the two inventions, when Zita came down the hall carrying a fair sized package which she tried hard to conceal.  Eva greeted her and continued down to the cellar, as Zita, with a sort of grim smile, left the house.

Eva came to the great door, pushed the secret spring, and in a moment was inside the gloomy place.  She went directly to the spot where the two inventions had been kept.  They were gone.

Alarmed, she rushed up-stairs.

Still Locke did not return.  Nor did any word come from him.  It was now very near to eight.  Eva decided to go, for surely Locke would be there.

When Zita arrived at the inventor’s, in her hands was still the mysterious package.  She carried it gingerly, then raised it to her ear.  From within it there came a faint ticking sound.  What was it inside?

She looked at her wrist-watch.  It was still some minutes before eight.  She knocked at the inventor’s door.

The inventor at once admitted her.  It was a neat little workshop in which every detail had been thought out with care—­the home, one might say, of a methodical workman.

The inventor manifested some surprise at seeing Zita, but politely asked her to enter, and offered her a chair.  Zita declined and plainly showed her nervousness.

“Will you please give this package to Mr. Locke and Miss Brent when they come at eight?” she asked.

Winters agreed and accepted the package, looking quizzically at her as he did so, just as he had earlier in the day.

Zita, unable to control her curiosity, burst out with the question uppermost on her mind.

“Why do you look at me in such a strange manner?” she queried.

The inventor merely turned his gaze away and shrugged.

“Mr Balcom tells me that you know the secret of my birth,” pressed Zita.

The inventor looked up quickly.  “Who did Mr. Balcom say you were?” he asked.

“He told me that I was Brent’s daughter,” replied Zita, keenly watching the aged face.

“Balcom lied to you,” hastened the inventor.

Already there was a ponderous tread on the stairs, but Winters did not seem to notice it.

“You are not Brent’s daughter,” he pursued, more slowly.

The door opened swiftly and an emissary stood framed there, a knife poised in his hand.  Behind him stood the Automaton.