Hi Marcia,

Thank you for contacting Mearto with your appraisal inquiry.
Argand lamps were usually sold in pairs; it's more desirable to collectors to have a pair rather than just a single, which keeps the value relatively modest.
Based on the photos and information provided, and subject to examination, this is:

A Neoclassical style brass single-arm argand lamp
with EM Duplex burner, mid 19th Century
Burner and reservoir with fleur-de-lys relief decoration, on a domed foot.
21 1/2 inches high, 13 1/2 inches wide, 6 3/4 inches diameter of base.
CONDITION: lacking glass (hurricane?) shade
PROVENANCE: inherited
$125-175*
*represents a fair-market value for auction purposes; retail or asking price may vary.

Please let us know if you have additional items to appraise, and thank you again for using Mearto.