ose its hold upon its work as readily as the hand
does. He was halfway to New York and had consciously bidden farewell to
the whole subject, when he suddenly startled those about him by rising
impetuously to his feet. He sat again immediately, but with a light in
his small grey eye which Mr. Gryce would have understood and revelled
in. The idea for which he had searched industriously for months had come
at last, unbidden; thrown up from some remote recess of the mind which
had seemingly closed upon the subject forever.

"I have it. I have it," he murmured in ceaseless reiteration to himself.
"I will go back to Mr. Challoner and let him decide if the idea is worth
pursuing. Perhaps an experiment may be necessary. It was bitter cold
that night; I wish it were icy weather now. But a chemist can help us
out. Good God! if this should be the explanation of the mystery, alas
for Orlando and alas for Oswald!"

But his sympathies did not deter him. He returned to Derby at once, and
as soon as he dared, presented himself at the hotel and asked for Mr.
Challoner.

He was amazed to find that gentleman already up and in a state of
agitation that was very disquieting. But he brightened wonderfully at
sight of his visitor, and drawing him inside the room, observed with
trembling eagerness:

"I do not know why you have come back, but never was man more welcome.
Mr. Brotherson has confessed."

"Confessed!"

"Yes, he killed both women; my daughter and his neighbour, the
washerwoman, with a--"

"Wait," broke in Sweetwater, eagerly, "let me tell you." And stooping,
he whispered something in the other's ear.

Mr. Challoner stared at him amazed, then slowly nodded his head.

"How came you to think--" he began; but Sweetwater in his great anxiety
interrupted him with a quick:

"Explanations will keep, Mr. Challoner. What of the man himself? Where
is he? That's the important thing now."

"He was in his room till early this morning writing letters, but he is
not there now. The door is unlocked and I went in. From appearances I
fear the worst. That is why your presence relieves me so. Where do you
think he is?"

"In his hangar in the woods. Where else would he go to--"

"I have thought of that. Shall we start out alone or take witnesses with
us?"

"We will go alone. Does Oswald anticipate--"

"He is sure. But he lacks strength to move. He lies on my bed in there.
Doris and her father are with him."

"We will not wait a minu