up to a restless pacing of the floor.  This was not usual with him.  Nor did he often indulge himself in playing on the piano as he did to-night, beginning with a few heavenly strains and ending with a bang that made the key-board jump.  Certainly something was amiss in the quarter where peace had hitherto reigned undisturbed.  Had the depths begun to heave, or were physical causes alone responsible for these unwonted ebullitions of feeling?

The question was immaterial.  Either would form an excellent preparation for the coup planned by Sweetwater; and when, after another hour of uncertainty, perfect silence greeted him from his neighbour’s room, hope had soared again on exultant wing, far above all former discouragements.

Mr. Brotherson’s bed was in a remote corner from the loop-hole made by Sweetwater; but in the stillness now pervading the whole building, the latter could hear his even breathing very distinctly.  He was in a deep sleep.

The young detective’s moment had come.

Taking from his breast a small box, he placed it on a shelf close against the partition.  An instant of quiet listening, then he touched a spring in the side of the box and laid his ear, in haste, to his loop-hole.

A strain of well-known music broke softly, from the box and sent its vibrations through the wall.

It was answered instantly by a stir within; then, as the noble air continued, awakening memories of that fatal instant when it crashed through the corridors of the Hotel Clermont, drowning Miss Challoner’s cry if not the sound of her fall, a word burst from the sleeping man’s lips which carried its own message to the listening detective.

It was Edith!  Miss Challoner’s first name, and the tone bespoke a shaken soul.

Sweetwater, gasping with excitement, caught the box from the shelf and silenced it.  It had done its work and it was no part of Sweetwater’s plan to have this strain located, or even to be thought real.  But its echo still lingered in Brotherson’s otherwise unconscious ears; for another “Edith!” escaped his lips, followed by a smothered but forceful utterance of these five words, “You know I promised you—­”

Promised her what?  He did not say.  Would he have done so had the music lasted a trifle longer?  Would he yet complete his sentence?  Sweetwater trembled with eagerness and listened breathlessly for the next sound.  Brotherson was awake.  He was tossing in his bed.  Now he has leaped to the floor.  Sweetwater hears him groan, then comes another silence, broken at last by the sound of his body falling back upon the bed and the troubled ejaculation of “Good God!” wrung from lips no torture could have forced into complaint under any daytime conditions.

Sweetwater continued to listen, but he had heard all, and after some few minutes longer of fruitless waiting, he withdrew from his post.  The episode was over.  He would hear no more that night.