Antique gas lamp?

[Cricket]

Hello, all...

     My lovely wife and I just purchased a house that was built in the 1880s or 90s. In the dining room is a fixture that appears to be quite old. My father had stopped in and told us it was worth some money.
     My question is this: can anyone identify this lamp and / or give an estimate of its value? If not, is there anyone who can at least point me in the right direction?

Thanks so much in advance.



Here's the lamp, you can see the valves if you look closely



And here's a closeup of the glass. Our realtor said it's Carnival Glass (?) I have no idea what that means.

[cogar]

Beautiful fixture but identifying it might be elusive because so many gas lights/gas-electric lights were produced. Some antique dealers specialize in gas lights and globes.

Or, there are books available: http://www.antiquelight.com/lighting_books.html

And "no", those globes are not "carnival glass" but just a standard type of frosted (opaque) globe. Note the 2nd and 4th center photo at this url:

http://www.antiquelampsupply.com/category/143/