Pocket barometer having 1¾” die struck and silvered dial, the outer altitude ring marked “Higher, Lower, +/- 1,000” with twin subscales divided in 100 ft and 50 ft increments the range 0 – 7,000 ft, the inner scale divided to inches of mercury with a range 23 – 31. Fine blued steel pointer, the upper dial with standard meteorological terms “Stormy,” “Rain,” “Change,” “Fair,” “Very Dry,” further annotated “Compensated.” The lower portion signed by the maker “Thomas Armstrong & Brother, Manchester & Liverpool” with serial no. “263.” Rotating bezel carrying the altitude ring, bevelled glass. Conventional 1” capsule driven movement by Negretti & Zambra with bimetallic compensation, unusual cast chassis with foundry mark “J.P. No 36.” Barrel form case, the verso with compensation port and screw. Pillar and suspension ring.
Contained within its original leather covered cream silk and very fine dark blue velvet lined presentation case. Snap closure on a button release.
Ostensibly a fairly ordinary looking instrument, the altitude scale however is very unusual – together with the obviously high quality movement and presentation case, this sets this piece apart from most. Though the brass case is similar in form to the other Armstrong pocket barometer showcased on this site, these instruments are, in most other respects, quite different. This one is certainly of substantially higher quality and probably intended for specialist application.
The lacquered finish slightly marked with some minor wear, dial and glass excellent, the presentation case leather outer with some marks staining and wear, the lid silk aged with some staining, the velvet to lower case excellent.
Fully serviced and conserved, this pocket barometer remains in absolutely original condition. A rare and very collectable piece.
Dimensions: 4” wide x 3¼” high x 1” deep
Stock No: PB0538