On a drippy day a few weeks ago I popped a videotape I had made into the VCR and was startled by the prominence of an unexpected sound coming from the TV's speakers.

The scenes were of downtown Salt Lake City in spring - median-strip flowers, buildings, streets, light traffic. But the audio track emphasized not the vehicular grumble (though that could be discerned in the background) or the scream of a fire engine or the honking horns of aggravated motorists.Instead, I heard birds. Lots of them - chirping away, yet invisible to the camera's eye.

I couldn't help but smile. Birdsong can do that.

"Think for a moment of the sounds we seldom think about, yet which constantly surround us," a colleague once wrote.

And occasionally, in part because of his recommendation, I try to do just that, especially when out and about for what Winston Churchill called "a constitutional."

I am a walker, a hiker. Treadmills and enclosed spaces hold no appeal, so even in winter, despite snow, rain, sleet and fog (though I do try to avoid them), I bundle up and head outside.

Luckily, my home is within a mile of the city's center yet very near the foothills. My options are varied. Depending upon the weather and other conditions, I can tromp to the tops of the hills, meander up a canyon or chart a course through a residential neighborhood or the steel-and-glass heart of the city itself. All of the routes have their appeals and their rewards.

Years ago, like other exercisers, I wore headphones, listening to the radio or to cassette tapes. Eventually, however, I decided to let my meditative thoughts have free reign and to attend only to the ambiance around me.

Occasionally something will catch my ear, reminding me of a radio jingle prominent locally in my childhood (on then-middle-of-the-road KCPX, I seem to recall). "The sounds of the city, the sounds that are heard, in Salt Lake City," the singers warbled, their voices supported by a variety of urban sound effects.

And in fact, not all of the "sounds of the city" are appealing:

The untempered screech of an air circulation unit of some kind atop a downtown bank.

The in-your-ear bass and roar of an intrusive car's sound system as the vehicle creeps down a busy street.

The crowds and cacophony of a mall food court.

The inescapable drone of traffic, even when you're indoors - or a few thousand feet above it on a hillside viewpoint.

But in counterpoint are happy times - moments worth seeking out - when urban sounds bring a smile to a hearer's face, contributing phrases to a metropolitan symphony:

A primordial, wordless conversation between faraway trains early on most any morning.

The muffled quiet after an overnight snowfall has blanketed the city.

The breeze through the trees and the briefly threatening flash-and-thunderclap approach of a summer storm.

The boisterous jangle of church bells on a Sunday morning. The Cathedral of the Madeleine, for instance, still looses a volley of bells before some services. Today we can only imagine the joyful noise recalled vaguely in Christmas carols.

The calming chimes of a carillon, as exemplified by the melodies that ring from the Utah State Capitol at the top of certain hours (noon, in particular). I first noticed melodies coming from the Capitol when I was a little boy. We lived a couple of miles away. I wondered then if it wasn't perhaps angelic music drifting to earth from the heavens.

And the twitter of finches and swallows, in the backyard shrubbery and in the middle of town - often a precursor to pleasant days down the road.