This is a very pretty antique miniature kerosene lamp in white frosted glass with a white frosted chimney in the Acorn pattern by the Beaumont Glass Company.  The lamp measures 3 1/2" in height to the top of the font and 8" in height if you include the white frosted glass chimney.  The pattern is pictured in the Smith - Miniature Lamps I Book on page 78 Fig. 121.  Condition is excellent with the top of the chimney having minor roughness.