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The call and the dying words narrow Holmes's inquiry to an Australian associated with Ballarat. James's account adds gray clothing, and access to the pool suggests someone familiar with the estate. Holmes then links this picture to the finer physical details obtained at the scene, explaining that his method rests on observing small things.
"It is obvious. And now, you see, I had narrowed the field down considerably. The possession of a grey garment was a third point which, granting the son's statement to be correct, was a certainty. We have come now out of mere vagueness to the definite conception of an Australian from Ballarat with a grey cloak."
「分かりきったことさ。こうして、調べる範囲がかなり狭まったのが分かるね。息子の証言を正しいと認めるなら、灰色の衣服を持っていることが、第三の確かな点になる。単に漠然とした話から、灰色のマントを着た、バララット出身のオーストラリア人という、はっきりした人物像へたどり着いたのだ」
"Certainly."
「確かに」
"And one who was at home in the district, for the pool can only be approached by the farm or by the estate, where strangers could hardly wander."
「しかも、その土地に通じた人物だ。池へは農場か地所を通ってしか近づけず、よそ者がそう簡単に入り込めるところではないのだからね」
"Quite so."
「そのとおりだね」
"Then comes our expedition of to-day. By an examination of the ground I gained the trifling details which I gave to that imbecile Lestrade, as to the personality of the criminal."
「そこへ、今日の現場行きが続く。地面を調べたことで、犯人の人物像に関する、あの取るに足らない細部が分かった。あのばかなレストレードに教えてやったものだよ」
"But how did you gain them?"
「でも、どうやって分かったんだい」
"You know my method. It is founded upon the observation of trifles."
「私のやり方は知っているね。ささいなことを観察するのが土台なのだ」