At the Architectural League of New York last week, the curator of architecture, design, and engineering collections in the Prints and Photographs Division of the Library of Congress, Ford Peatross, conversed with photographer John Margolies about the estimated 75,000 photos the latter has taken over the last 30 years of travel across America.

Special projects manager Gregory Wessner introduced the program, saying that Mr. Margolies has documented aspects of the “vernacular” environment that others have often ignored: signs, storefronts, gas stations, motels, and restaurants.

Mr. Peatross opened by showing images from the Library of Congress’s searchable Web site, which contains hundreds of thousands of photos and drawings from the Historic American Buildings Survey and other sources. He said surprisingly its fastest growing audience was kindergarten through 12th graders. Mr. Peatross spoke about how the Library of Congress has collaborated with W.W. Norton on a series of “visual sourcebooks” in architecture, design, and engineering. Books, with accompanying CD-ROMs, have been completed on barns and canals, while there are books planned on lighthouses, bridges, cemeteries, libraries, and porches.

Mr. Margolies spoke next, as the audience viewed a tiny fraction of his 15,000 and 20,000 photographs. He also showed images of printed ephemera (menus, maps, matchbooks, postcards) showing everyday life in America as seen through material objects, roadside attractions, and building traces.

While tourists often train their cameras on celebrated structures (Empire State Building, Statue of Liberty), Mr. Margolies has photographed more humble structures from drycleaners to car wash and automobile repair shops. He said it was not just important for “high style” buildings to be documented, but gas stations, fast food joints, and other ordinary, everyday structures where people spend a lot of their time. These places are not incidental but show part of the American identity, he said. He called his wide range approach “the alpha-omega from state capitols to hamburger stands.”

Amidst the flow of images of motels, signs, and theaters, the Knickerbocker learned a couple of facts. Frank Lloyd Wright, who built the Guggenheim Museum, also designed a gas station in Cloquet, Minn. And Buffalo Bill built a hotel in Wyoming named for his daughter, Irma.

At one point in the talk, large concrete slabs from old drive-in theaters filled the screen. “They define the borders of towns,” Mr. Margolies said, adding that they were like “America’s Stonehenge.”

Cultural exclusivity can be glimpsed through some artifacts: When showing pictures of shore resorts, Mr. Margolies flashed a copy of an old beach pass, allowing a beachgoer to swim at Belmar beach.

Toward the end of the program, Mr. Margolies showed a photo of a large sphinx head. “This is what sold me on miniature golf. I was on Highway 17. I looked up and saw that and knew miniature golf was for me.” (He coauthored a book on the subject.) He showed windmills and other obstacles that miniature golf players face. The audience laughed when he also showed a photograph of a large Buddha statue at one hole. “Nothing,” he said, “is sacred in miniature golf.”

During audience questions, Mr. Margolies said he preferred to take his photographs very early in the morning to get the best light. He prefers to have no cars, no people, and a blue sky in his photos.

An audience member asked what reaction from those around him as he took photographs. He told an anecdote about the time he was photographing a Shell gas station in Hamilton, N.Y., around 1977. A bystander asked him “Are you preserving that for posterity?” He replied “yes,” but didn’t fully understand the question. Then he discovered the next morning, the gas pumps were to be torn up.

Regarding the pictures he has taken, Mr. Margolies said he was not nostalgic: “I don’t wish things are still like that. I’m just glad that things were like that, and that I could make a record of these things.”

gshapiro@nysun.com