original early 20th century ornamental cast iron interior residential or commercial wall thermometer, manufactured by the powers regulator co., chicago, il. the circular panel is comprised of very delicate and intricately designed filigree or openwork with the original copper-plated finish largely intact. a surrounding band features repeating pierced quatrefoils. the centrally located yellow brass thermometer is original and in working condition. a small bronze strap enclosure or guard protects the mercury-containing reservoir. the temperature scale is lightly incised on the panel containing the thermometer. measures 12 inches in diameter.