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Watson first thinks of escorting Kate, then decides she need not go at all. His position as Isa's medical adviser gives him influence over the missing man. He promises to find Isa, put him in a cab, and have him home within two hours.
There was the case, and of course there was but one way out of it. Might I not escort her to this place? And then, as a second thought, why should she come at all? I was Isa Whitney's medical adviser, and as such I had influence over him. I could manage it better if I were alone. I promised her on my word that I would send him home in a cab within two hours if he were indeed at the address which she had given me. And so in ten minutes I had left my armchair and cheery sitting-room behind me, and was speeding eastward in a hansom on a strange errand, as it seemed to me at the time, though the future only could show how strange it was to be.
事情はそういうことで、取るべき道はもちろん一つしかなかった。私が彼女をそこへ連れていけばよいのではないか。いや、考えてみれば、そもそも彼女が行く必要などあるだろうか。私はアイザ・ホイットニーの主治医なのだから、彼も私の言うことなら聞くだろう。一人で行く方がうまく運べるはずだった。教えられた住所に本当にいるのなら、二時間以内に馬車で家へ送り届けると、私は固く約束した。こうして十分後には、私は肘掛け椅子と明るい居間を後にし、ハンサム馬車で東へ急いでいた。そのときも奇妙な使いだと思ったが、どれほど奇妙なものになるかは、その後にならなければ分からなかった。