It sounds vaguely like Irresistible 2, as in that it's set around the time period you stated (around 1915?), although, Byron wasn't caught by anyone -- but he was spyed on.
In the scene, Tommy took on a pair of sexy babes, Tiffany Blake and Erica Idol, in a hot threesome that ended with him spraying off a load across Blake's tummy, while Erica stroked him off. Alexis Greco, looking beyond gorgeous, spyed on the three while they fucked.
Byron banged out like 300 movies between 82 and 85 so it's pretty much up in the air as to which one it was. I'm sure he made a number of period piece porno movies back in the day, since they seemed to be all the rage then.