"Because I have been looking up a little information with reference to the Ko-Katana and its uses. Now, Okasaki is the name of a j.a.panese town.

Family names almost invariably have a topographical foundation, referring to some village, river, street, or mountain, and there may be thousands of Okasakis. Then, again, it was the custom some years ago for a man to be called one name at birth, another when he came of age, a third when he obtained some official position, and so on. For instance, you would be called Spring when you were born, Summer when you were twenty-one, Autumn when you became a policeman, and Winter when you reached your present rank."

"Oh, Christopher!" cried the detective. "And if I were made Chief Inspector?"

"Then your t.i.tle would be 'Top Dog' or something of the sort."

Mr. Winter a.s.similated the foregoing information with a profound thankfulness that we in England do these things differently.

"Why are you so interested in Mr. Okasaki?" he inquired.

"I will answer your question by another. Why was he so interested in the Ko-Katana?"

"That is hardly what I told you, Mr. Brett. He professed to be interested in the crime itself. But now I come to think of it, he did ask me to let him see the thing."

"And did you?"

"Yes; I wanted all the information I could get."

"My position exactly. Let us go to Scotland Yard."

The famous Black Museum has so often been the subject of articles in the public press that no detailed description is needed here. It contains, in gla.s.s cases, or hanging on the walls, a weird collection of articles famous in the annals of crime. It is not open to the public, and Brett, who had not seen the place before, examined its relics with much curiosity.

The detective exhibited a pardonable pride in some of them, but his companion damped his enthusiasm by saying:

"This is a depressing sight."

"In what way?"

"British rogues are evidently of low intelligence in the average. A bludgeon and a halter make up their history."

"There's more than that in a good many cases."

"Ah, I forgot the handcuffs."

"Well, here is the Ko-Katana," said Winter shortly.

The barrister took the fateful weapon, not more deadly than a paper-knife in appearance, and scrutinised it closely.

"It has not been cleaned," he said.

"No, it was left untouched after the doctor withdrew it from the poor young fellow's breast."

Brett produced a magnifying gla.s.s. Beneath the rust on the blade he thought he could distinguish some j.a.panese characters in the quaint pictorial script adapted by that singular people from the Chinese system of writing.

He brought the knife nearer to the window and carefully focussed it. Then he produced a note-book and made a pencil drawing of the following inscription:

[Ill.u.s.tration]

Winter watched him with quiet agony. He had never noticed the signs before.

"Mr. Okasaki did not tell you what these scratches meant?" inquired the barrister.

"No. He did not see them."

"Sure?"

"Quite positive. Of course, it is very smart on your part to hit upon them so quickly, but what possible purpose can it serve to find out the meaning of something carved in j.a.pan more than fifty years ago, at the very least?"

"I do not know. It is very stupid of me, I admit, but I have not the faintest notion."

"Does it make the finding of Okasaki more important?"

"To a certain extent. We want to have everything explained. At present we have so little of what I regard as really definite evidence."

"May I ask what that little is?"

"Sir Alan Hume-Frazer was murdered with a knife produced by a man like David Hume, whom 'Rabbit Jack' saw standing beneath the yews. Not much, eh?"

Winter shook his head dubiously.

"If Sir Alan were shot instead of stabbed," went on the barrister, "the first thing you would endeavour to determine would be the calibre and nature of the bullet. Why not be equally particular about the knife?"

"But this weapon has been for fifty years in Glen Tochan. Its history is thoroughly established."

"Is it? Who made it? Whose crest does it bear? What does this motto signify? If you wanted to kill a man would you use this toy? Why was not the sword itself employed?"

"That string of questions leaves me out, Mr. Brett."

"I am equally uninformed. I can only answer the last one. The sword is intended for suicidal purposes, the Ko-Katana for an enemy. This is a case of murder, not suicide."

The detective wheeled sharply on his heels, thereby upsetting Charles Peace's telescopic ladder.

"You suspect Okasaki!" he cried.

"My dear fellow! Okasaki is, say, five feet nothing. The murderer is five feet ten inches in height. j.a.panese are clever people, but they are not--telescopes," and he picked up the ladder.

Winter grinned. "You always make capital out of my blunders," he said.

"Pooh! My banking account is limited. Let us go. The moral atmosphere in this room is vile."

Outside the Central Police Office they separated, Brett to pay some long-neglected calls, Winter to hunt up Capella's movements and initiate inquiries about Okasaki.

The detective came to Brett's chambers at five o'clock, in a great state of excitement.

"Thank goodness you are at home, sir." he cried, when Smith admitted him to the barrister's sanctum. "Capella is off to Naples."

Naples, the scene of his marriage! What did this journey portend? Naught but the gravest considerations would take him so far away from home when he knew that David and Helen were reunited.