1930s vintage Coleman gas lamp model 56B, with beautiful brass font marked "The Sunshine of the Night". It's about 6 1/2" in diameter across the base, 18" tall overall.
It hasn't been used in many years, and smells clean, no fuel residue. This looks tight and leak free, and we see no reason why it wouldn't work. It's missing the turn knob on the burner adjustment, but we saw no other problems.