aluable, and his next care must be to find her and learn her story.

She might of course save him the trouble by herself coming forward. She
would be almost certain to see an account of the murder in the papers,
and even if not, her father's disappearance would inevitably lead her to
communicate with the police.

But Willis could not depend on this. She might, for example, have left
the previous day on a voyage, and a considerable time might elapse
before she learned of the tragedy. No; he would have to trace her as if
she herself were the assassin.

He looked at his watch and was surprised to learn that it was after
one o'clock. Nothing more could be done that night, and with a sigh of
relief he turned his steps homewards.

Next morning he was back at the Yard by eight o'clock. His first care
was to re-examine the taxi by daylight for some mark or article left by
its recent occupants. He was extraordinarily thorough and painstaking,
scrutinizing every inch of the floor and cushions, and trying the door
handles and window straps for finger marks, but without success. He went
over once again the clothes the dead man was wearing as well as those in
the suitcase, took prints from the dead man's fingers, and began to get
things in order for the inquest. Next, he saw Dr. Horton, and learned
that Mr. Coburn had been killed by a bullet from an exceedingly small
automatic pistol, one evidently selected to make the minimum of noise
and flash, and from which a long carry was not required.

When the details were complete he thought it would not be too early to
call at the Peveril and begin the search for Miss Coburn. He therefore
sent for a taxi, and a few minutes later was seated in the office of
the manageress. She repeated what Matthews had already told him, and he
personally interviewed the various servants with whom the Coburns had
come in contact. He also searched the rooms they had occupied, examined
with a mirror the blotting paper on a table at which the young lady had
been seen to write, and interrogated an elderly lady visitor with whom
she had made acquaintance.

But he learned nothing. The girl had vanished completely, and he could
see no way in which he might be able to trace her.

He sat down in the lounge and gave himself up to thought. And then
suddenly an idea flashed into his mind. He started, sat for a moment
rigid, then gave a little gasp.

"Lord!" he muttered. "But I'm a blamed idiot. How in Hades did