theory has been substantiated at every point."

"It has, Inspector," I agreed; "but I don't know that the fact
enlightens us very much; for it merely indicates that the man whom you
declare to be the central figure of the conspiracy is only a secondary
figure, and that all we know about the person whom we may regard as
the prime mover is that she is a woman--apparently possessing
supernormal eyes which glitter in the dark. She is also associated in
some way with the figure of Bast. What is her relation to Dr. Damar
Greefe and in what way is she interested in the destruction of the
Coverly family?"

Gatton smoked in silence for a while, staring at me reflectively,
then:

"If we knew that, Mr. Addison," he said, "we should know all there is
to know about 'the _Oritoga_ mystery.' But I think we should have
advanced a long step towards this information if we could apprehend
the Eurasian. Of course we have gathered up all the ragged details of
the Red House incident: I refer to the carter who delivered the crate
and collected it in the morning, of the caterer who supplied the
supper and so forth. As I had fully expected, none of the evidence
helped us at all."

"'The voice,'" I began.

"Exactly! The same 'voice' beyond a doubt, and the whole thing worked
through the means of district messengers and others, telephonically
instructed. No one appeared throughout, Mr. Addison."

"Yet," I said deliberately, "there was one point at which some one
_must_ have appeared--"

"Yes," he interrupted, "some one dragged the body out of that
supper-room, down to the garage, and packed it in the crate."

"You have definitely convinced yourself that the telephone device was
practiced there?"

"Beyond question. Haven't you seen the exchange number? That plug
where at some time a gas-fitting had been fixed up in the wall--you
remember?--proved on investigation to communicate with an empty room
adjoining. The gas cylinder was placed there of course, and the
telephone in the recess of the supper-room, where, fastened in by the
velvet curtain, any one using the poison installation would be
suffocated almost immediately."

"Good God, Gatton!" I cried. "It's a horrible business, and for my own
part I have no idea what the next step should be."

"I'm a bit doubtful, myself," admitted Gatton; "but you know the line
of reasoning which has led me to the conclusion that these people
possess a base of operations somewhere in this district.