Tell me, Helen, said she, have you ever heard anyone whistle in the
dead of the night?
Never, said I.
I suppose that you could not possibly whistle, yourself, in your
sleep?
Certainly not. But why?
Because during the last few nights I have always, about three in the
morning, heard a low, clear whistle. I am a light sleeper, and it has
awakened me. I cannot tell where it came from perhaps from the next
room, perhaps from the lawn. I thought that I would just ask you
whether you had heard it.
No, I have not. It must be those wretched gipsies in the plantation.
Very likely. And yet if it were on the lawn, I wonder that you did
not hear it also.
Ah, but I sleep more heavily than you.
Well, it is of no great consequence, at any rate. She smiled back at
me, closed my door, and a few moments later I heard her key turn in the
lock.
Indeed, said Holmes. Was it your custom always to lock yourselves in
at night?
Always.
And why?
I think that I mentioned to you that the Doctor kept a cheetah and a
baboon. We had no feeling of security unless our doors were locked.
Quite so. Pray proceed with your statement.
I could not sleep that night. A vague feeling of impending misfortune
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