A silver and very early, possibly one of the very first pocket watch sized aneroid barometers by Negretti & Zambra no. 575 c1863

Silver pocket barometer having 1⅞” silvered and engraved dial, the barometric scale calibrated in inches of mercury with a range from 16” – 31” divided down to 1/20th, fine blued steel pointer, rotating bezel with mounted barb index, bevelled glass.

The finely poised and finished movement with steel braced bridge marked “10”, micro height adjustment, blued screws. Decorated chassis struck with number “10,” cock and spindle mounted to sub-chassis, driven from a single 1⅛” nickel alloy capsule tensioned on a coil spring. All contained within a semi barrel form and ribbed sterling silver case, hallmarks to bow and pendant. Calibration port with sliding cover to verso.

Presented in burgundy leather over timber, green silk and velvet lined case, snap closure on a button release.

Condition: The subject of a full service, conservation, and calibration under laboratory conditions, see performance chart from dynamic test. The movement working presentably well across the barometric range. The dial very crisp, the silver case bright and clean.

Comments: A very unusual instrument with an exceptionally wide scale (16″ is the equivalent of almost 15,000ft), this is one of the first pocket watch sized instruments constructed and almost certainly a special order. These early instruments were assembled by a specialist team of selected personnel from the Negretti & Zambra workforce, this evidenced in the very fine making of the movement.

Aspects common to these 1st series instruments include the hand engraved address, attributes in construction and finishing of the movement, and what was probably an optional dust shutter over the calibration port.


Very much an important collector’s piece.