Auto dim mirrors

[tech_ed]

I just got a 1996 Grand Cherokee Limited...it's fully outfitted with the works including auto dimming mirrors. The inside rearview mirror autodims...and, according to the previous owner, the outside drivers mirror dims.
Now here's the problem. The driver's side outside mirror has a bronze tint to it. It seems to be some kind of fluid sandwiched between the mirror and a piece of glass/plexiglass. I know it's a liquid because it is slowly draining into somewhere. The mirror now shows the upper 3rd as a regular mirror and the lower 2/3rds with bronze tint. If you push in on the bronzed side, you can squeeze the fluid up...and even create bubbles.
My question is...how does this system work? To dim, does it pump the bronze fluid in that sandwiched area of the mirror? Or what? It's very confusing. I've never seen anything like it before. Any help?
Thanks
Ed
web/gadget guru