That electric belt reminds me of the diseased ramblings of Lanz von Liebenfels. Who, when peddling his particularly interesting brand of racism mixed with freaky excursions into the world of “Biblical exegesis”, came up with the wacky theory that humans were originally “electric supermen”, and lost this status through miscegenation. I kid you not.
His magnum opus (you can find it online if you’re diligent, and enjoy the batshit insanity thereof) bears the wonderfully Pythonesque title of, wait for it:
Theozoology, or the Account of the Sodomite Apelings and the Divine Electron
Oh, incidentally, this was the individual whose writings helped to propel Hitler on the path leading to the Holocaust.
Liebenfels asserted that the only path that would lead to (surprise, surprise) blond Aryans regaining their rightful status as “electric supermen”, was ruthless cultivation of “racial purity” (translation: lots of inbreeding). We all saw what that did to the Habsburgs. He had an inventive streak when it came to racial insults aimed at those outside the Aryan pale, referring to purportedly “inferior” races as “castrated Chandalas” and “beastmen”.
I suspect Dr Sanden’s bizarre contraption pre-dates Liebenfels by a good decade or more, it looks like the sort of quasi-steampunk gadget that would have been doing the rounds of various odd catalogues in the 1880s or early 1890s, unless of course you have a date for the advert that reveals otherwise.
Though it didn’t take long after the discovery of electricity, for assorted humans to figure out ways of introducing it into kinky sex - look up “violet wands” for possibly the canonical example.