Hi Tony,

Thank you for contacting Mearto with your appraisal inquiry.
Some states and countries restrict the sale of items containing mercury, which may make selling this tricky.
Based on the photos and information provided, and subject to examination, this is:

An antique George III or George IV inlaid rosewood barometer and thermometer
made by Manticha & Co., London, late 18th/early 19th Century
Surmounted by a broken pitch pediment centering an acorn(?) finial, the engraved brass plaque, over a waisted body terminating in a circular base.
38 inches long
PROVENANCE: inherited
$200-300*
*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.