My mother lives in a sort of technological time capsule. She has no email address; in fact, she’s never used the Internet. She does not even have voice mail or an old-school answering machine. That latter fact means that every once in a while when I call her, I hear an incredibly rare sound — a busy signal. Given the preponderance of voice mail today, one almost never hears that anymore. A busy signal belongs to an interesting and growing category: Sounds that are becoming technologically obsolete.

That’s why I really dug this story in the Fort Wayne Journal, profiling the guy who heads up the Smithstonian’s effort to collect and preserve recordings of all these extinct sounds. Check it out:

Inside a bombproof vault a few blocks from the White House, Dan Sheehy is surrounded by audio ghosts: the clickety-clack of typewriters, the tumble of glass bottles inside a soda machine, a 1960s-era telephone ring.

Here, sonic blasts from the past are entombed in a hodgepodge of vinyl records, compact discs and reel-to-reel tapes. “We are a museum of sound,” said Sheehy, whose job is to preserve America’s acoustic heritage for an obscure branch of the Smithsonian Institution.

Sounds are like smells, he says. They can transport the listener to another time and place. The buzz of an airplane propeller sends Sheehy’s mind back to hot afternoons in 1950s Bakersfield, Calif., playing in the yard while aircraft sputtered overhead. “The sound immediately triggers memories of time and temperature,” he said.

(Thanks to Boing Boing for this one!)