Page:The Greene Murder Case (1928).pdf/396

 you—to know that the revolver in the china-closet was held in place by a Stiefelknecht, or bootjack."

He closed the volume but held it on his lap.

"There, unquestionably, is where Ada got the suggestion for Rex's murder. She and Rex had probably discovered the hidden passageway between their rooms years ago. I imagine that as children—they were about the same age, don't y' know—they used it as a secret means of correspondence. This would account for the name by which they both knew it—'our private mail-box.' And, given this knowledge between Ada and Rex, the method of the murder becomes perfectly clear. To-night I found an old-fashioned bootjack in Ada's clothes-closet—probably taken from Tobias's library. Its width, overall, was just six inches, and it was a little less than two feet long—it fitted perfectly into the communicating cupboard. Ada, following Gross's diagram, pressed the handle of the gun tightly between the tapering claws of the bootjack, which would have held it like a vise; then tied a string to the trigger, and attached the other end to the inside of Rex's panel, so that when the panel was opened wide the revolver, being on a hair-trigger, would discharge