Could perseverance be an appropiate theme for "The Pit and the Pendulum?"While reading the story I felt that the narrator's consistent effort to...

I think this is a very interesting theme to explore. However,
the best arguments are ones that look at both sides, especially arguments against what you are
trying to show. Therefore, you will want to think through the following aspects of the story. I
agree that perseverance is shown in particular with the incident with the pendulum, however how
can we argue that the narrator shows perseverance when he is exploring the cell he is in and
literally stumbles across the pit? There appears to be more luck in this incident of survival
than anything else. You could likewise argue that he survives the pendulum only because of a
blind response to a terrifying fear.

However, the oppositie of this
would be the calculated way in which the protagonist seems determined to survive. He explores his
cell scientifically, and then carefully constructs a plan to free himself from the
pendulum:

Nor had I
erred in my calculations--nor had I endured in vain. I at length felt that I was
free.

Such quotes, referring to the
"calculations" of the protagonist, suggest that perseverance is indeed a very evident theme of
this great short story.