“History Detectives” (8 p.m., PBS, check local listings) moves into Independence Day mode. Now in the second week of its new season, the series employs appraisers, researchers and historians to examine artifacts and heirlooms, and the family legends that have grown around them.

In one segment, a woman from Charlotte, N.C., asks the detectives to determine whether the commemorative pin given to her great-grandfather contains metal drawn from the real Liberty Bell in Philadelphia.

The search for the source of the pin takes “Detectives” to 1895, when the Liberty Bell was sent to the Cotton States Exposition in Atlanta. The trade fair was organized to demonstrate that Atlanta, part of a New South, was open for business, and the loan of the Liberty Bell was clearly a gesture of reconciliation between the North and the South, 30 years after the conclusion of the Civil War.

According to news records unearthed here, the Liberty Bell was a real hit at the fair. On a more serious note, the fair also provided a venue for an important address by Booker T. Washington.

It would be remiss to reveal whether the woman’s pin contained metal from the bell. To find out, you’ll just have to tune in.

Two additional segments concern a $6 note issued in the opening months of the American Revolution, a piece of American currency that predates the Declaration of Independence.

There is also a British 10-shilling note from 1942 containing the autographs of most of the major British and American civic and military leaders. To add to its mystery, it contains the cryptic phrase “Short Snorter.” We soon discover the origins of the autograph collection and the meaning of “Short Snorter,” something that would be no mystery to a veteran of World War II.

“Detectives” is always rewarding – a nice combination of treasure hunting and scholarship that asks us to think about the history that might be lurking in our own attics and drawers.

Tonight’s other highlights

¢ Kyle knows more than he can say about a local murder mystery on “Kyle XY” (7 p.m., Family).

¢ Spatulas sizzle on two hours of “Hell’s Kitchen” (7 p.m., Fox).

¢ Eyewitnesses describe their close encounters on the two-hour “UFOs – Seeing Is Believing” (7 p.m., National Geographic), followed by “The Real Roswell” (9 p.m.).

¢ Willing women decades apart on “Age of Love” (8 p.m., NBC).

¢ A blind girl with an overbite and a boy with an amputated leg get some help on “Extreme Makeover” (8 p.m., ABC).

¢ Marc’s insurance company throws up roadblocks on “Big Medicine” (8 p.m., TLC).

¢ An effort to save face on “The Closer” (8 p.m., TNT).

¢ Bill frets about his testimony and possible blackmail threats on “Big Love” (8 p.m., HBO).

¢ “Simon Schama’s Power of Art” (9 p.m., PBS, check local listings) profiles Bernini.

¢ A case gets personal on “CSI: Miami” (9 p.m., CBS).