WITHIN thirty minutes after Ackerman had received Stella’s message that she had found the secret entrance to the house he was waiting for her at the door of the vault as she had suggested.

He had entered by the rear wagon road and passed into the shrubbery without attracting the attention of the servants.

She showed him the way to the underground passage through the niche in the rear of the vault, and in ten minutes Ackerman entered the hall through the panel under the stairs.

Stella, who had returned to the house across the lawn, watched the panel slowly open at his touch and her eyes gleamed with a cold, hard light as she saw reenacted in imagination the tragedy of her father’s death.

The detective made an accurate diagram of the hall, measured carefully the distance of the secret door from the chair in which the Judge had been found, and re毛xamined the ballroom and all its possible exits and entrances.

Stella returned to the entrance of the vault and placed a padlock and chain on its iron door while Ackerman again entered the underground passage and spent two hours alone, making the most minute examinations and measurements of every track to be found at any point from the door of the vault to the panel in the wainscoting. The work of measurement was rendered easy by the accumulation of soft earth in the bottom of the underground way from the action of the water which had soaked through the brick ceiling and walls.

He discovered the footprints of eleven different men besides the dainty mark of Stella’s little shoe made the night before.

He returned to the hall and asked her permission to come from time to time and continue his study of the grounds.

“Certainly,” she answered eagerly. “And your discoveries?”

“Confirm so far my theory of the crime,” he answered quickly. “The assassins undoubtedly entered the house by this secret passage, committed the cri............