Baylor Theatre’s “An Experiment With An Air Pump” may reference an 18th-century scientific apparatus in its title, but the play works as a centuries-spanning time machine at the same place with many of the same actors and a murder in the middle.

The 1998 play by Shelagh Stephenson (a “Downton Abbey” co-writer) imagines two scientific investigations, each on the brink of a new century. On New Year’s Eve 1799, doctor and scientist Joseph Fenwick (James Cobb) is experimenting with testing how long a dove can live without air, work that might have human implications as he finds in discussions with a physician Armstrong (Noah Alderfer) and an ethically sensitive scholar Roget (Lucas McCutchen). On the periphery to his work is his family, wife Susannah (Meredith Bennett) and daughters Harriet (Kalyn Constable) and Maria (Morgan Maxey), as science is a realm for men and not women. It’s also not the realm of servants like Isobel (Hannah Rosenkranz).

Fast forward 200 years, in the same house on the same night, and things have changed. Ellen (Bennett) is the scientist, thinking of a career change to work with geneticist Kate (Constable), but in a field somewhat controversial because of its use of pre-embryonic material.

She and her husband Tom (Cobb), laid off from his teaching post, are moving out of their family homestead, the former Fenwick estate. Their plans for the future and the ethics involved area under discussion with home surveyor Phil (Noah Alderfer), when an old box of bones are discovered — bones that link the two stories beyond gender issues and moral questions.

“It’s three parts social drama and one part murder mystery,” said Baylor graduate student and director Laura Nicholas, who’s directing the play as part of her master’s degree requirements.

The two stories take place in the same space, but in time periods that alternate, forcing quick costume and character changes for her core cast. “It goes back and forth between the two time periods, but I think the audience will see the connections,” she said. Mature subjects are handled, yet there’s humor worked into the script to keep it entertaining, she said. “The great thing about the play is that it doesn’t take a stance on either side of the issues,” she said. “The spirit of the play is to encourage dialogue.”