Newton's Eyeball

Before the famous experiment with the prism, before he discovered the rules of gravitation (although probably at about the same time that the apple apocryphally fell on his head), Isaac Newton performed a brief experiment in anatomical optics.  Paraphrasing from his own notes, he took a small knife (a bodkin), and pushed it into his eyeball as far back around the curve as possible, in order to see the effects it had upon his vision.

Now, to be fair, the accompanying diagrams do make it look as if A) the bodkin was blunt, possibly the "large needle" instead of the "dagger" sense, and B) although it's not clear, it might have been outside the eyelid.  Rather than something more last-act Oedipal, it may have just been an extreme version of rubbing your eyes hard in order to see the pretty lights.

Still, this is clearly a degree of dedication to scientific inquiry that is seldom equalled in this day and age, or frankly in any other.  Which, honestly, is as it should be.  I mean really.  A true scientist would poke the eyes of a random sampling of other people, careful not to hint at any potential expected outcome.  Hadn't he ever heard of a single-blind study?