Barometers Realm

This barometer is part of the private collection of our friend and fellow collector Heikki Vähäsarja (Finland). All photographs were kindly provided by him.

This Early Decorative Aneroid, dating from approximately 1850, is an exceptionally early aneroid barometer manufactured by the Hamburg instrument maker Deutschbein, one of the first German craftsmen to adopt the aneroid barometer shortly after Lucien Vidie’s invention. The instrument belongs to the earliest period in the development of aneroid barometry and is of particular historical importance as one of the first commercial aneroid barometers produced specifically for the British export market. Its combination of elaborate decorative styling with state-of-the-art mechanical engineering makes it a remarkable representative of the earliest generation of mercury-free barometric instruments.

The case is cast from zinc alloy and finished with a bronzed surface. It features an expressive sculptural form inspired by the decorative traditions of the late Rococo period. The deeply modelled relief is richly ornamented with asymmetrical scrollwork, acanthus leaves, shell motifs, and flowing foliate designs that create a vivid impression of continuous movement across the surface. The original bronzed finish, intended to imitate aged bronze or antique gilding, accentuates the depth of the relief and enhances the sculptural quality of the composition. At the top of the case is a metal suspension loop for wall mounting, harmoniously integrated into the overall silhouette.

The dial is made of heavy white card and displays the restrained graphic design typical of the mid-nineteenth century, entirely free from unnecessary ornamentation. It is protected by a flat mineral glass with a neatly bevelled edge, fitted into a substantial brass bezel that serves both protective and decorative purposes.

The barometric scale is comparatively compact and calibrated in London inches of mercury, indicating that the instrument was intended for the British export market. Its measuring range extends from 28 to 31 inches of mercury. Traditional English weather indications are printed around the outside of the barometric scale, while corresponding weather descriptions in German appear on the inside. This bilingual arrangement is a particularly interesting feature of the instrument, reflecting its export destination while preserving its connection with German manufacturing traditions.

A small mercury thermometer occupies the lower portion of the dial and is graduated in degrees Réaumur. The thermometer is enclosed within an elegant glass tube terminating in a spherical mercury reservoir and serves as an important complement to the barometer, allowing simultaneous observation of air temperature. The use of the Réaumur scale was common throughout much of continental Europe during the mid-nineteenth century and further emphasizes the instrument’s continental origin despite its English barometric scale.

The instrument is based upon one of the earliest versions of Lucien Vidie’s aneroid mechanism, preserving the characteristic engineering features of the first generation of aneroid barometers. The sensitive element is an evacuated copper aneroid capsule, whose deformation under changing atmospheric pressure is converted into mechanical motion. Mounted above the capsule on supporting posts is the massive cast-iron operating lever. This lever bears against an externally mounted coil spring, which defines the operating characteristics of the sensitive element while providing the restoring force that returns the mechanism to its equilibrium position.

From the end of the principal lever, the motion is transmitted through an inclined connecting rod to a compact bell-crank lever mounted on carefully made pivot bearings with minimal friction. Here, the minute displacement of the aneroid capsule is amplified further before being transferred via a fusee chain to the pointer arbor. Borrowed from fine horological practice, the fusee chain allowed the extremely small movements of the sensitive element to be converted into smooth pointer rotation with virtually no loss of motion, while simultaneously reducing friction and minimizing lateral loads on the pointer spindle.

Of particular interest is the overall architecture of the movement, which is characteristic exclusively of the earliest generations of aneroid barometers. The engineering concepts developed by Lucien Vidie during the first years following his invention remain clearly visible: the massive operating lever, the external coil spring, the sequence of progressively acting levers, and the fusee chain together form a complex yet remarkably efficient kinematic system that subsequently became the foundation for the further evolution of aneroid barometry.

This instrument is an outstanding example of an early European aneroid barometer from the middle of the nineteenth century, combining the pioneering mechanics of the first aneroids with the rich decorative aesthetics of its period. Its English export scale, bilingual weather indications, Réaumur thermometer, and one of the earliest forms of the Vidie mechanism make it not only a rare historical witness to the birth of aneroid barometry, but also one of the most expressive examples of the high standard achieved by German scientific instrument makers during the mid-nineteenth century.