Since I have been asked to furnish a story about the Liberty Bell, here it is.

We went to visit the Liberty Bell in his / her / its home in Old City Philadelphia. So as we were standing in front of it along with fifty other Liberty Bell admirers, one Taco Bell admirer who was kind of lost and one KFC admirer who was completely lost, I heard the guide say, "So here is the famous crack in the Liberty Bell which is", and he paused dramatically, "pretty hard to find". And the crowd around me roared in laughter. I also roared somewhat but after roaring for a couple of seconds, I stopped roaring and said to my wife, "I don't get the joke. The crack is really hard to find. In fact, to be honest, I can't see a single crack anywhere on the bell". Here is what the Liberty Bell looked like :

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Then, after trying hard to find a crack on the Liberty Bell for some more time, I gave it up. I then probed the guide's comment for any hidden humorous connotations but all I could come up with were a number of connotations which, due to their vulgar implication, couldn't possibly be what he was referring to. So basically I gave up and then we left and went to do something else.

Now it appears that the Liberty Bell actually looked like this from the side opposite from where I was standing.

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I get the joke now.