Wikipedia has this nice photo of a historical re-enactor dressed as an 1800's patent medicine broker.
Clark Stanley, likely the most (in)famous snake oil peddler,
After the passage of the pure food and drug act in 1906 championed by Teddy Roosevelt, it was examined and found to have no medicinal value. He was fined and it was removed from the market. Stanley's product didn't even contain any snake! It was mineral oil and some other extracts.
I’ve been thinking, how would you actually make that oil? Is it like olive oil, in the sense that you simply put dead snakes in a big press and squeeze out the virgin snake oil? Snakes contain lots of water too, so the goo you get that way is probably pretty far from oil.
What if you have to use a more modern approach? Use hexane or another organic solvent to separate the oil from the rest. Then just evaporate the hexane, and you’re left with the oil. Maybe you would have to combine both methods.