What's buried in Franklin Park? A new discovery and an old photo are two clues that dig into the history of old Boston.

The photo is stamped with the year 1893 and shows a girl reaching into a fountain for a cup of water. There is no visible stone fountain like this in Franklin Park today, but some think it could be buried there in the dirt.

A worker with the Emerald Necklace Conservancy, which helps with the upkeep of the park, discovered the slab of stone between two trees in Franklin Park and made the connection with the old photo. It raises questions about what lies beneath the ground.

Karen Mauney-Brodeck, president of the Emerald Necklace Conservancy, has a theory about what happened to the fountain in the old photo.

"It's possible that the area was intentionally filled," she said. "Parks do change over time."

Her other theory is that the fountain simply became obsolete.

"It's also possible that the idea of a shared-cup water fountain fell out of favor for concerns about diseases," she said.

The discovery of the stone slab and the connection to the black and white photo has led to excitement to solve the mystery and could lead to a dig.

"It might be something that the city will choose to do, and we also want to make sure that we have an archaeologist on site to make sure that's done carefully," Mauney-Brodeck said.