Rockwood Mansion in Wilmington is beginning restoration of its rare, historic “gas house.”
The cave-like structure built into the side of a hill was used to make acetylene gas, which lit lamps in the Rockwood mansion around the turn of the 19th century, according to Rockwood Museum Director Philip Nord.
Gas houses became obsolete when electricity became widely available. According to County officials, few gas houses are thought to survive today.
Nord says it wasn’t until recently that the museum knew what the structure was.
“It was all overgrown and everything, and nobody really knew what it was. It looked like the entrance to a gold mine actually and … just sort of ominous,” he said.
According to Nord, a machine that produced gas was kept in the gas house—far away from the main house—because acetylene was prone to explosions.
The restoration of the gas house will include debris cleanup, masonry repair, fencing and lighting and is expected to be done later this year. It will then be open to visitors.
Madeline Dunn with the Division of Historical and Cultural Affairs says the gas house will be documented in an amended nomination for the National Register of Historic Places—which will tell a more complete story of the Rockwood property by including outbuildings, biographic stories and social context.
“It is going to be fantastic. These researchers have done a phenomenal job,” she said.
Nord says he aims to apply for National Historic Landmark designation for Rockwood once the amended National Register nomination is complete.
According to county officials, restoration of the gas house is being funded by a $7,000 grant from the Eastern Brandywine Hundred Coordinating Council.
Rockwood was built in the 1850s by Quaker merchant-banker Joseph Shipley.
The park and mansion museum are managed by the County. Museum admission is free the first Sunday of every month.
