A nitrate film reel with nine minutes of footage capturing San Francisco two weeks after the 1906 earthquake surfaced at the Alemany Flea Market, and this rare find reveals a startlingly clear view of a city in ruins.

Film historians say the series of clips were shot by the early San Francisco film studio the Miles Brothers and is a bookend to their most famous work "A Trip Down Market Street," a 13-minute silent film shot from a cable car days before the earthquake.

The new footage makes a similar trip down Market Street, from Fifth Street to the Ferry Building, but in this newly found footage many of the buildings lining the city's main thoroughfare have fallen to the ground.

The reel also includes clips showing a mob of horse wagons and carts and people waiting to get on a ferry to cross the Bay to Oakland, a blighted City Hall with its dome nearly destroyed, and damaged buildings being blown up with dynamite.

Film historian David Kiehn confirmed the origin of the film and has spent the past eight months preparing a digital version that will be premiered at the Niles Essanay Silent Film Museum in Fremont on April 14 (tickets are $5 to $7).

"Miles Brothers footage shot after the earthquake is extremely difficult to find," Kiehn says. "They shot more footage than anyone else after the earthquake, almost 7,000 feet of it, I believe. Almost two hours of footage and practically none of it survived. This nine-minute piece is the biggest segment that I've seen anywhere and another great part of this footage is it re-creates 'A Trip Down Market Street.'"

VIDEO: Footage from the Miles Brothers "A Trip Down Market Street" taken before the 1906 earthquake

Kiehn also made headlines in 2010 when he challenged the Library of Congress' 1905 date on "A Trip Down Market Street," and using weather and vehicle registration records proved it was shot days before the big earthquake. His discovery was featured on "60 Minutes."

Nitrate film is highly flammable and delicate and Kiehn built an optical printer to take images of each frame and convert the film into a digital format.

"It's a very slow process, running it through the machine," he says. "It took 20 hours, an hour or two at a time. I had to be there at the machine nursing it through. There are 8,600 frames throughout the film. It took a few seconds to copy each frame."

The film was originally purchased by David Silver, who collects vintage cameras, at the Alemany Market in 2016, and he says he bought it from seller who was "standing there looking through a length of it with a lit cigarette hanging from his lips."

"We were an inch away from it going up in flames," Silver says.

On Jan. 18, 2017, Silver posted news of his find on the Facebook Group San Francisco Remembered founded by Nick Wright, writing, "For those of you who scream and flee in panic at the mere mention of nitrate, have no fear, the film is in splendid condition, no outward signs of chemical deterioration, and surprisingly little smell when I opened the Pathe can."

Nick's brother, Jason Wright, a photography historian and collector living in England, saw the posting, purchased the reel from Silver and enlisted the help of Kiehn.

"Eighty or 90 percent of it is completely unseen footage," says Jason, who owns Silver Shadows Gallery Ltd. "And 10 percent is much better quality [than the previously known footage]."

ALSO, New photos uncovered from 1906 S.F. earthquake

Jason explains that it's known this film was created as the Miles Brothers mentioned it among footage advertised for sale in the New York Clipper on June 30, 1906.

"I am just glad we could save this important film by getting it in the right hands," he says. "David Kiehn has done a fantastic job of digitizing it and now we just have to decide the best way to show it to the people of San Francisco after the initial screening on April 14."