Joyful noise recorded for posterity

History used to be silent. We don’t know what Julius Caesar sounded like, or how the actors performed when Shakespeare’s plays debuted at the Globe theatre. In 1877, inventor Thomas Edison captured the words “Mary had a little lamb” on a tinfoil cylinder phonograph, and the era of recorded sound was born. “Save Our Sounds,” an installment of “Save Our History” (7 p.m., History), recounts the efforts of archivists and historians to preserve treasures of recorded sound for future generations.

The Smithsonian Institution and the Library of Congress are crammed with thousands of records, magnetic tape, waxed cylinders and other media dating back to the late 19th century. They can play a copy of a speech President McKinley delivered on the day before his assassination in 1901. There’s a field recording of an Indian ceremony made in 1890. We can still hear narratives by Southern blacks born into slavery, immigrant tales and countless folk songs.

Unfortunately, many of these recordings are disintegrating. Old wax cylinders are especially vulnerable to changes in temperature. After more than half a century, magnetic tapes tend to disintegrate and old records crumble. “Save Our Sounds” shows how experts repair these treasures and transfer them to a more durable digital format. And while digging through their old archives, curators have turned up some recordings they didn’t even know they had. One archivist discovered an acetate disc containing Woody Guthrie’s very first performance of “This Land is Your Land,” including two extra verses it was thought he had never recorded.

Viewers who want to contribute to the “Save Our Sounds” effort can bid on special, autographed musical instruments available on eBay through January 2, 2003. For more information, log onto www.ebay.com/saveourhistory.

Tonight’s other highlights

  • Michael Richards brings his Kramer-like physical comedy to the 1997 legal comedy “Trial and Error” (7 p.m., Fox), co-starring Jeff Daniels.
  • On back-to-back episodes of “CSI” (CBS), high school revenge (7 p.m.), two bodies in a culvert (8 p.m.).
  • David and an Outsider enter a boxing ring to vie for Marion’s affections on “Dinotopia” (7 p.m., ABC). This marks the last scheduled episode of this fantasy series.
  • Scheduled on “PrimeTime” (8 p.m., ABC): the Dilley sextuplets.
  • Christmas may be over, but not Christmas movies. A security guard forces two shoplifters (Mary Stuart Masterson and Lauren Pratt) to be incarcerated in a store in the 1997 comedy “On the Second Day of Christmas” (8 p.m., Lifetime).
  • “The Sopranos” (HBO) repeats the first two episodes of the just-completed fourth season. Tony and Carmela confront a poor economy (8 p.m.) and a grieving Meadow enters therapy (9 p.m.).
  • Four witnesses testify to a woman’s disappearance on “Without a Trace” (9 p.m., CBS).
  • As winter blows into town, Carter has a heart-to-heart with his icy mom (Mary McDonnell) on “ER” (10 p.m., NBC).

Series notes

Phoebe goes to extreme lengths to attend a Sting concert on “Friends” (7 p.m., NBC) … Wrestling on “WWE SmackDown!” (7 p.m., UPN) … Sissy goes to charm school on “Family Affair” (7 p.m., WB).

The staff feels overextended on “Scrubs” (7:30 p.m., NBC) … Joel mulls a personal sacrifice for his sister’s sake on “Do Over” (7:30 p.m., WB).

Grace feels torn between her handsome new boyfriend (Harry Connick Jr.) and her promise to make a baby with Will on “Will & Grace” (8 p.m., NBC) … A deadly double date on “Good Morning, Miami” (8:30 p.m., NBC) … Sixty minutes of improvisation on “Jamie Kennedy Experiment” (8 p.m., WB).