Robert M. Panoff

The goal of this project is to explore the range of answers to a simple question: what is the period of the pendulum that Poe describes in his story, "The Pit and the Pendulum"? Depending on how careful the reader is, this very simple question leads to a lively discussion on how to compute the period of a very physical pendulum whose amplitude is clearly not "small." What, for instance, might be the smallest and largest answers that students can construct consistent with the information in the story?

To wit, the pit occupant tells us:

"[the ceiling] was some thirty or forty feet overhead... In one of its panels...was the painted figure of Time as he is commonly represented, save that, in lieu of a scythe, he held...a huge pendulum."

"I now observed - with what horror it is needless to say - that [the pendulum's] nether extremity was formed of a crescent of glittering steel, of about a foot in length from horn to horn; the horns upward, and the outer edge evidently as keen as that of a razor. Like a razor also, it seemed massy and heavy, tapering from the edge into a solid and broad structure above. It was appended to a weighty rod of brass."

"Notwithstanding its terrifically wide sweep (some thirty feet or more)..."

As the prisoner estimates that "ten or twelve vibrations would bring the steel in actual contact with my robe," how much time does the prisoner have to escape?

Clearly, this is not a point mass suspended from a massless, inextendible string. But properly analyzed and carefully computed, the computationally-enhanced reader, too, can exclaim with the exultant prisoner, "Nor had I erred in my calculations - nor had I endured in vain!"