Mytton Antiques - Jerrard Nares has dated this piece to the 1850s.
The dial with weather indications relating to the barometric pressure.

The main body mounted with a thermometer, and the lower body with a raised ogee edged cistern, finished to the bottom with a concave mould to repeat the form of the pediment.
The Barometer by J.H.Steward, 66, The Strand, London.
Height 38 inches
Width 4 1/2 inches
Depth 3 inches
Circa 1850
Mytton Antiques - Jerrard Nares has dated this piece to the 1850s.
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