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Holmes explains that he knows the staircase has seventeen steps because he has observed it. He then offers Watson a new puzzle: an unsigned note that arrived with the last post. Holmes asks him to read the thick pink notepaper aloud. The note also lacks a date and an address.
"Quite so! You have not observed. And yet you have seen. That is just my point. Now, I know that there are seventeen steps, because I have both seen and observed. By the way, since you are interested in these little problems, and since you are good enough to chronicle one or two of my trifling experiences, you may be interested in this." He threw over a sheet of thick, pink-tinted notepaper which had been lying open upon the table. "It came by the last post," said he. "Read it aloud."
「そうだろう!きみは観察していないんだ。それでいて、見てはいる。そこが肝心なところだよ。さて、私は十七段あることを知っている。見て、しかも観察しているからだ。ところで、きみはこういうちょっとした謎に関心があるし、私のささやかな経験をひとつふたつ記録してくれてもいるから、これにも興味がわくかもしれないね」彼は、テーブルの上に広げて置いてあった厚手で淡い桃色の便箋を一枚、こちらへ放ってよこした。「最終便で届いたんだ」と彼は言った。「声に出して読んでくれたまえ」
The note was undated, and without either signature or address.
その手紙には日付がなく、署名も住所もなかった。