I've been using the Civ3 Rifleman for that unit, and yes, I call it Adventurer. (Great minds think alike!)

Now that we've got those 3 new cool musket infantry type units the Rifleman makes for a good Adventurer animation.
I've got it set as a hidden nationality unit with two movement points. I made the unit for my civ for the sole purpose of "flushing out" industrial era units that I added to the game. I found I was adding all these cool unit animations for AI civs but I would never see them! With the adventurer, I'd land one on foreign soil (made 'em cheap) and watch all the cool AI units come out to attack it.
I originally got the idea from that "Lost World" syndicated TV show. It looks pretty cool fighting Arab Riders, Assassins, Ninjas, Samurais etc. Anyway...that's what I use it for and the Rifleman anim looks pretty good to me. If someone can come up a Rifleman with a pith helmet or something all the better.
Now that I think about it...Wheel Gator's Boer rifleman would make a great Adventurer.
As far as the Victorian era sci-fi theme...I've put BlueO's Battle Angel in as a UU for the Aztecs. I call it the Condor Archer and give her one MP with All Terrain As Roads. No sound for the Run animation and it's pretty cool. She silently glides in over the mountains, jungle, whatever and attacks with a deadly barrage of arrows. She's actually the unit I made the Adventurer for. I put the Condor Archer in the game and I'd
NEVER see one. I pop an Adventurer or two on Aztec soil and here come the Condor Archers! Sweet.
Just some ideas...