A scarce special order Forecasting Aneroid barometer No. 9091 and desk forecaster compendium by Negretti & Zambra, London c1920

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Aneroid barometer having 3¾” silvered and die struck dial, the barometric scale calibrated in inches of mercury with a range from 28” to 31” divided to 1/20th, the upper part marked “Forecasting Aneroid,” the lower “Compensated,” signed by the maker “Negretti & Zambra, London” with serial “No. 9091” and maker’s “N&Z” logogram. Fine blued steel pointer, bevelled glass with bezel operated index.

First quality well finished Vidie pattern movement driven from a single 2” nickel silver capsule, all contained within a three part spun case comprising bezel, main body marked to the periphery with altitude adjustments to 3,000 feet, and rotating back plate incorporating Whiteside-Cook’s patent. Locking crown setting datum mark. Calibration port to verso.

The 4¾” diameter brass desk forecaster of standard pattern with selection for wind direction, rising, falling, or steady pressure, barometer pressure and season, and signed “Negretti & Zambra.” Black crackle finished verso with ball jointed easel stand.

All contained in a mid-brown pigskin over timber framed, green velvet lined travel case, soft green velvet dividing insert, 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 well with good sensitivity.

In fine original condition, the barometer dial clean and crisp, the glass clear and chip free, the brass case retaining virtually all its original lacquered finish, some tarnishing and minor wear. The locking crown working correctly, the bezel rotating smoothly, the back plate with smooth operation and locking securely.

The desk forecaster retaining virtually all its original lacquer and black crackle finish, the moving elements free and operating correctly. The swinging, folding easel stand in good condition.

The travel case the subject of some re-construction and restoration, structurally sound, retaining virtually all its original pigskin covering and green velvet interior. The ribbons later replacements.

Comments: A very good and now very hard to find compendium. In these days when condition is so eagerly sought after, of such compendia examined this is one of the very best and indeed would be hard to beat.

Made to special order in small numbers, this is the iconic partner to the well known Weather Watch, and a truly wonderful commentary on early C20th Britain. A treasure.

NB: The image shown of the instructions is taken from an original leaflet held in the Vavasseur Archive. A digital PDF of this image will be provided with this instrument.