With your eyes closed, you heard pounding hooves, the tread of marching feet, the rat-a-tat-tat of a machine gun and the creaking door to "The Inner Sanctum."
When you looked, there was Owens Pomeroy thumping rubber plungers against his chest, rattling a frame of wooden blocks laced together, tapping a stick on a cigar box, and slowly opening and closing a rusty hinge.
"This is the theater of the mind, of imagination," said the 61-year-old retired silver engraver from Hampden who learned sound effects techniques as a young gofer at radio station WFBR.
The show was presented recently for about 40 students at Loch Raven Senior High School by Mr. Pomeroy and other members of the Golden Radio Buffs of Maryland, one of nationwide network of clubs devoted to preserving and promoting the "Golden Age of Radio," roughly 1930 to 1950.
The Loch Raven students, members of teacher Neal Haynie's drama class, are studying old-time radio and plan to produce a comedy program as a class project.
Listening to the corny jokes of Fibber McGee and Molly, to Jack Benny's violin screeching as he sparred verbally with Mary Livingston and Rochester, to William Conrad's growl as Marshal Matt Dillon of "Gunsmoke," or to Orson Welles as "The Shadow" asking "Who knows what evil lurks in the hearts of men?" took old-timers on a "Sentimental Journey" -- as that song played -- to the time when radio was the source of home entertainment.
But for most of the teen-agers seated on the auditorium stage --like an old-time radio audience -- it was a new experience, like watching a chapter from a history book come to life.
Children of the television age, most of them know only the radio of disk jockeys, newscasts and talk shows, not the radio of drama, comedy, suspense broadcasts, soap operas, children's shows and quiz shows. In a mock quiz show, the name Henry Aldrich meant nothing to one girl, nor did the name of Fibber McGee's ditsy wife nor Jack Benny's instrument.
"It was interesting, different from the entertainment of today," said Marc Smith, a senior. "It's like nothing I ever saw before."
Terry Sitaras and James Kahle, also seniors, said they have listened to old radio programs for years on tapes available commercially but hadn't before gotten the impression of attending a broadcast.
Television is an immediate visual medium that delivers its images and vanishes, Mr. Pomeroy said, but the fascination for radio was that it required listeners to use their imaginations. That helps explain why people tend to remember characters and programs decades later, he said.
Mr. Pomeroy and 72-year-old Loretta Levy of Randallstown, a longtime community theater actress, teamed up on either side of the microphone, reading from scripts as if they were broadcasting to demonstrate how it went in the old days.
Sound effects engineers, whose "illusion of reality" was vital to the success of any radio program, remain a key element in movies, Mr. Pomeroy said. They add sounds after films have been shot because the equipment to capture clearly every needed sound cannot be carried to location.
Gene Leitner, who co-founded the Buffs with Mr. Pomeroy in 1972, said the club has recordings of more than 10,000 local and network broadcasts from the Golden Age, about 2,000 of them cataloged. Club members, about 157 locally and nearly as many elsewhere in the United States and Canada, may use the tapes for the price of postage and handling.
Orson Welles' legendary "War of the Worlds" remains the most famous program ever, and "The Shadow" is the most consistently popular program, said Jerry Michael, 50, of Dundalk, the club librarian.
Mr. Leitner, 56, of Dundalk said the Buffs are part of a nationwide cooperative network of clubs devoted to preserving, promoting and perpetuating the art of broadcasting in the Golden Age, the "sounds" of radio.
"I think nostalgia is the key thing. Every generation that is exposed to old-time radio loves it," he said.
The club honors local and network radio personalities, actors, announcers and musicians at its bimonthly meetings and occasional dinners. The personalities return the favor by regaling club members with recollections of life in the broadcast industry.
The Buffs also have a standing exhibit at the Museum of Industry on Key Highway in Baltimore. Mr. Pomeroy presents the "road show" there monthly, including programs broadcast through old radios.
The best moments, members said, is when children lie on the floor, listening intently just as they did themselves years ago.
"We're preserving the past for them," Mr. Leitner said.
Another local group, the Mid-Atlantic Antique Radio Club, devotes itself to collecting and preserving the actual radio sets.
Allan Caplan, 48, of Pikesville, one of the youngest Buffs, has interests as a collector of radio artifacts such as the 16-inch disks on which programs were transcribed before the invention of wire and tape recording.
In Baltimore, WITH (1230 AM) broadcasts two different old-time programs nightly on a syndicated show, "When Radio Was," beginning at 11:05 p.m.