Motor aneroid having 2¾” die struck silvered dial, outer bezel activated altimetric scale calibrated in metres with a range from 0 – 2400m (approx. 7,874ft), and divided to 20m. Inner barometric scale calibrated in centimetres of mercury with a range from 60cm – 78cm and divided to 2mm. The upper part marked in a crescent “Baromètre Holostérique,” surrounding the PHNB logogram, and “Compensé.” The lower part with retailer’s details, G. Viallet, Marseille. The outer dial (not visible when assembled) marked “02 Aut.” Fine blued steel pointer, heavy bevelled glass set in a knurled bezel with deep high-polished reflector ring. Conventional though very fine quality movement driven from a single 1⅜” capsule tensioned on a C spring, stamped “35.”

All contained within a drum form aluminium case with top flange drilled for panel mounting. Compensation port to verso.

Condition: The subject of a full service, restoration and conservation, the movement working exceptionally well with good transition and sensitivity. The altimetric ring with slight losses and minor discolouration. The dial centre clean and vibrant, crisp overall. The glass with minor marks and a slight scratch, no visible chips. The aluminium case oxidised overall.

Comments: This is a very interesting piece. At first glance it might be taken as an early aircraft altimeter, but seemingly dated 1902, that could not be the case as the Wright Brothers flew in 1903. Another option would be for ballooning, but this is unlikely since balloons flew considerably higher than 8,000 feet. This really only leaves an application for automotive fitment which makes this one of the very first altimeter barometers designed for a car.

The quality is exceptional with a very finely constructed movement.