The Tell-Tail Heart by Edgar Allan Poe published 1843.

True, nervous, very, very dreadfully nervous I had been and am, but why will you say that I am mad?

The disease had sharpened my senses, not destroyed, not dulled them.

Above all was the sense of hearing acute.

I heard all things in the heaven and in the earth. I heard many things in hell. How then am I mad?

Harken and observe how healthily, how calmly I can tell you the whole story.

It is impossible to say how first the idea entered my brain,

but once conceived, it haunted me day and night. Object there was none. Passion

there was none. I loved the old man. He had never wronged me. He had never given me insult. For

his gold I had no desire. I think it was his eye. Yes, it was this. He had the eye of a vulture, a pale blue eye with a film over it.

Whenever it fell upon me, my blood ran cold and so by degrees very gradually I made up my mind

to take the life of the old man and thus rid myself of the eye forever.

Now this is the point. You fancy me mad.

Mad men know nothing, but you should have seen me. You should have seen how wisely

I proceeded. With what caution, with what foresight, with what dissimulation I went to work. I was never kinder to the old man during the week

before I killed him. And every night, about midnight, I turned the latch of his door and opened it. Oh, so gently.

And then, when I had made an opening sufficient for my head, I put in a dark lantern all closed, closed, so that no light shone out and then I thrust in my head.

Oh, you would have laughed to see how cunningly I thrust it in.

I moved it slowly, very, very slowly,

so that I might not disturb the old man's sleep.

It took me an hour to place my whole head within the opening so far that I could see him as he lay upon his bed.

Huh, would a madman have been so wise as this?

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