LYNN – A manhole cover is a manhole cover unless it has BSSTRY imprinted across the center. Then it’s history, according to engineering history buff Stefan Wuensch.”I’ve never come across another Bay State Street Railway Company cover,” he said. “Chances are this is very unique.”A handful of local historians have been working to save pieces of the Belden Bly Bridge, which workers were to begin dismantling Sunday to make way for a permanent structure. Built in 1913, the Belden Bly Bridge is one of the oldest cantilevered bridges in the country. Work has wrapped up on the $13.6 million temporary bridge and will begin on the permanent bridge soon.”I went down to take pictures of the bridge for posterity. I’m a fan of engineering,” Wuensch said. “I happened to look down and realized what was at my feet.”The manhole cover, which is set in the sidewalk leading to the bridge itself, dates back to 1912, the same age as the bridge, Wuensch said. The Bay State Street Railway Company ran street cars north and south of Boston in the early 1900s, including the state’s very first electric trolley right in Lynn.”They were already in Lynn and they were looking around for a really steep route to electrify, and they picked Rockaway,” he said.With an 8 percent slope uphill and a 12 percent slope headed down the other side, Wuensch said the street posed a great test to the company, one it passed. But by 1919 the company went bankrupt and disappeared, according to the MBTA’s history of electrification.Most people walking over the Route 107 manhole cover would not know its significance but because he is an admitted engineering geek, Wuensch said he knew immediately its historic value.”It’s in immaculate condition, hopefully it won’t be damaged by any heavy equipment rolling over the bridge,” he added.Wuensch isn’t looking to walk away with the manhole cover, however. Aside from the fact it weighs an estimated 200 pounds, he said he mostly wanted to make people aware of it in the hopes that someone would rescue it.”It’s not necessarily for me to grab,” he said. “But if the museum doesn’t have a place for it I’d gladly be a custodian ? I just want to make sure it gets saved.”Historical Commission member Calvin Anderson said the museum is planning to take some relics from the 100-year-old bridge including the two control panels that open and close the bridge. One bears a large General Electric nameplate and both are believed to be original to the structure.It was Anderson, in the fall of 2012, who began reaching out to people in the hopes that someone would step forward and preserve at least some pieces of the bridge. He said he would hate to miss an opportunity to save history, “once it’s gone it’s gone.” The problem is the commission has no building or budget and is in no position to actually accept any of the pieces, so he got others, like the museum and Lynn Vocational Technical Institute alumni Ron Beckett interested in the project.Anderson said Beckett plans to have several pieces carried off, and once they are deleaded, cleaned and shined they will be stacked into sculpture for LVTI.And although he isn’t taking anything home, Anderson vowed to be there to watch the bridge come down. After putting more than a year’s worth of work into the project he said, “it’s something like my baby being delivered. I’ll be there. I’ll be there all day.”