This is a heavy oil lamp and was told it came from a railroad dining car. It is marked on the bottom and there is a number on the back of the mounting plate. There is a large dent on the area which holds the oil as shown in the 5th photo and the rim above that is slightly bent. The very top also has a slight bend.
Please ask for additional photos if needed as I included 12 here. The stem which operates the wick does move as it should. Height of lamp excluding the glass shade is 13.25. Depth from wall is about 9.5. The item "Antique Heavy Brass Railroad Car Oil Lamp Adams & Westlake Company Chicago" is in sale since Wednesday, May 29, 2019.
This item is in the category "Collectibles\Transportation\Railroadiana & Trains\Hardware\Lanterns & Lamps". The seller is "dord-us2014" and is located in Nellysford, Virginia. This item can be shipped to United States.