Miniature pocket barometer having 1½” silvered and engraved dial, the outer crown-activated rotating altimetric scale calibrated in feet with a range from 0 – 8,000ft and divided to 100ft, inner fixed barometric scale calibrated in inches of mercury with a range from 23” – 31” and divided to 1/10”. The upper part marked with standard meteorological wording and “Compensated,” the lower portion marked “Gibson Limited, Belfast.” Fine blued steel pointer beneath bevelled low domed glass. Conventional 1st quality movement, dated 1898, driven from a single 1” nickel alloy capsule tensioned on a C spring.
All contained within a semi barrel form silver case, smooth side ribs with hallmarks for silver, 1897 and silversmith Lewis Nightingale. Engine turned verso with calibration port and cartouche containing viscount’s coronet, monogram or entwined initials, and the years “1874” and “1899.” Hallmarked silver extension post and suspension ring.
Condition: The subject of a full service, conservation and calibration under laboratory conditions, the pocket barometer altimeter working well with good sensitivity and progression, see performance chart. Overall very crisp, the dial with very faint marks at 6 o’clock, the crystal chip-free. The silver case with slight marks.
Comments: Silver pocket barometers are perhaps amongst the most attractive of these instruments, and certainly the hardest to find. This piece has the added interest of the viscount’s coronet, the initials either forming the monogram of the viscount, or possibly the initials “B” and “E”, and the date range indicating that this may have been a 25 year anniversary present. Our research continues.
A very attractive and unusual pocket barometer with historical interest. Very collectable.
Dimensions: 1¾” diameter x ⅝” deep
Stock No: PB1855