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While waiting in the inn room for night, Watson asks Holmes about what they observed at the house. Watson says that nothing besides the bell-rope seemed especially strange. Holmes brings up the ventilator and makes an unexpected observation, inviting Watson to reconsider how the two objects are connected. The scene begins from this carefully established point.
"You speak of danger. You have evidently seen more in these rooms than was visible to me."
「きみは危険だと言うが。きみはあの屋敷の部屋で、私に見えた以上のものを見たのは明らかだね」
"No, but I fancy that I may have deduced a little more. I imagine that you saw all that I did."
「いや、ただ、私はもう少し多くを推理したかもしれないと思う。きみも私が見たものはすべて見たと思うが」
"I saw nothing remarkable save the bell-rope, and what purpose that could answer I confess is more than I can imagine."
「呼び鈴の紐のほかには目立ったものは何も見なかったよ。あれが何の役に立つのか、正直、見当もつかない」
"You saw the ventilator, too?"
「通風口も見たかい?」
"Yes, but I do not think that it is such a very unusual thing to have a small opening between two rooms. It was so small that a rat could hardly pass through."
「ああ、だが、二つの部屋の間に小さな開口部があるのが、そんなに珍しいこととは思えないがね。ネズミが通れるかどうかというほど小さかったし」
"I knew that we should find a ventilator before ever we came to Stoke Moran."
「ストーク・モランに来る前から、通風口があるはずだと分かっていたよ」
"My dear Holmes!"
「おいおい、ホームズ!」