Why Is the Liberty Bell Tapped Thirteen Times Every Fourth of July?
Every Fourth of July, the Liberty Bell participates in a ceremony that seems impossible for a bell famous for being broken. At two in the afternoon in Philadelphia, it is gently tapped thirteen times, once for each of the original thirteen states. Junior members of the Descendants of the Signers of the Declaration of Independence traditionally help perform the ritual, while other bells around the country may ring in response.
The careful tapping protects the bell from further damage. Its enormous crack prevents it from being rung normally, but the light strikes allow it to remain part of the national celebration.
There is an irony hidden inside the ceremony. Although the Liberty Bell has become inseparable from American independence, historians have found no evidence that it rang on July 4, 1776, when Congress approved the Declaration. There is not even evidence that it rang four days later, when the Declaration was publicly read in Philadelphia. The famous tale of the bell announcing independence developed long afterward.
The annual tapping is also much newer than the Revolution. A nationwide Independence Day bell ringing observance was promoted in 1963, following a proposal by writers Eric Hatch and Eric Sloane. Congress endorsed the idea, calling for bells across the country to ring at the same moment.
The Liberty Bell therefore commemorates July 4 through a carefully created modern tradition. America’s most famous bell does not ring, and probably never announced independence. Yet thirteen quiet taps now speak for the thirteen states that began the country.
Source: The Liberty Bell, National Park Service - Let Freedom Ring Bell Tapping Ceremony, National Park Service

Jefferson Memorial seen across the Tidal Basin at dusk in Washington, D.C
Source: By Joe Ravi