It's not online, but the best campaign I ever ran personally was a supers game set in 1900.
The way I did it:
1) Use the setting for Space:1889 as the main default.
2) Add those additional Wellsian and Vernesian elements you want.
3) Crib liberally from pulp fiction, especially sci-fi/fantasy pulp like John Carter or Leigh Brackett's Skaith stories, tales of Atlantis, etc.
4) Find some other sources: Wild, Wild West (TV show and movie), Kung Fu (original series), League of Extraordinary Gentlemen, Gotham by Gaslight, William Gibson's Difference Engine, Sherlock Holmes stories... Even things that aren't strictly period can get incorporated with some clever rewriting- Hellboy, Wu Shu martial arts flicks and James Bond movies can be rewritten to make fine period adventures.
5) Put your own spin on it: in mine, the Martians were addicted to opium...and it made them into psychotic workhorses (think Alien Nation). I also stole stuff from Michael Moorcock's Bastable books (large colonial air-navies, a mysterious warlord from the East, etc.).
6) Listen to your players. If they get inspired- and almost anyone knows about this era to get stoked about this- their imaginations will spur a lot of your campaign. I was trying to figure out how to work in Atlantis, and one of my players turned in a PC background based on an anime character who was an adolescent amnesiac Atlantean with a whip. Before long, they were caught up in the struggles between Atlanteans and Lemurians (and the surface world besides- thank you Namor, the Sub-Mariner stories).