When Jeff Altman stumbled across a film canister at a South Side estate sale with the words “Chicago” and “Print 1” on it, he was curious enough to plunk down $40 for it.

“I was intrigued as to what might live inside,” Altman said.

He found 32 minutes of vintage footage produced by the Film Council of the Chicago Board of Education, showcasing Chicago while a narrator describes facts and statistics surrounding the scenes.

Over the next two weeks, Altman, who works in commercial post-production, inspected the reel and fixed small tears and other issues before scanning the film and turning into a digital video, a process that took between six and eight hours to complete.

“It was really interesting to me,” Altman said. “It’s actually kind of mysterious as well. For me, the most surprising part was just how long it was and all the cool and unusual views of the city that it gave.”

He said the film could have been geared toward tourism or used to entice companies to come to Chicago or even as a form of education in classrooms.

“I can’t really figure out what the intended purpose of the film was,” he said.

Chicago Public Schools says the video was released between Jan. 8 1945 and Sept. 15, 1946.

John Howatt, who is credited as the Business Manager of the Board, was elected on Jan. 8, 1945, according to Lauren Hoffman, the deputy press secretary at Chicago Public Schools.

The narrator, Johnnie Neblett, died on Sept. 15, 1946, she said, meaning the film had to have been released at some point during the two dates.

This isn't the first time elements from Chicago's past have been unintentionally uncovered.

In 2011, John Maloof discovered tens of thousands of negatives from Vivian Maier at an auction.

Maier, who settled in the Chicago area in the early 1950s, worked as a nanny and took thousands of stunning photographs on city streets on her days off, along with additional photos during visits to New York, Canada and Florida.