Barometers Realm

The Bourdon barometer from Imperial Russia, circa 1865, housed in a brass case, is designed in a classic drum form, featuring a bayonet fitting bezel and a back plate with a shuttered calibration port. The case, measuring just 10 cm in diameter, highlights the metal’s dual role as both functional and aesthetic. The brass, with its warm golden hue, seems as if it was crafted to reflect the ideas of strength and refinement. At the center of the case, illuminating the structure, is an elegant, fine-toothed gear mechanism, so intricately detailed that the eye is drawn to its complex geometry. This mechanism is completed by the brass Bourdon tube, which gently wraps around the gearwork in a semicircle. This is not merely a mechanism but a kind of visual rhythm that invites contemplation.

The blued steel pointer creates a striking contrast with the brass, highlighting the symbolic difference between the materials: while brass represents stability and brilliance, steel stands for precision and cold calculation. The pointer glides over the scale with a smoothness that inevitably evokes a sense of the passage of time — inevitable and unrelenting. The scale, marked in London inches of mercury and divided into twentieths of an inch, conveys the precision of measurements, yet its texture and subdivided markings seem to underscore a striving for absolute accuracy.

Printed on the dial is the inscription "metallic barometer," flanked on either side by references to the awards Bourdon's invention received at the Paris Exhibition of 1849 (Bourdon and Richard's patent, Gold Medal) and at the Great Exhibition in London in 1851 (Council Medal). The barometer is signed with the engraved initials "EB"—Eugène Bourdon—as well as "RICHARD A. PARIS," representing Richard of Paris.

The values for standard weather indications are written in pre-revolutionary Russian orthography, carrying not just information but a powerful visual presence. All words are in capital letters. In the weather readings "В.ДОЖДЬ" ("HEAVY RAIN") and "В.СУШЪ" ("HEAVY DRYNESS"), the letter "В" (meaning "great") emphasizes the magnitude and power of the weather phenomena, symbolizing the majesty of nature and its dominance over human lives.

An interesting and extremely rare feature of this barometer is its adjustable dial. The face consists of two discs: the outer one, which displays the weather terms, is fixed, while the inner disc with the barometric scale is movable. The inner disc can be rotated relative to the outer one. For the weather terms to make any sense, the manufacturer must shift their positions depending on where the barometer will be used. Moreover, based on a large number of observations, the manufacturer has to determine the average barometric pressure at a given location and place the word “Change” at that specific level. With a dial where the barometric scale can be rotated along the weather terms, the owner of the instrument can adjust the markings himself when moving from place to place, aligning “Change” with the appropriate pressure level.

This feature is especially important for this barometer, as its small size — only 10 centimeters — indicates that it was intended for travel. It is known that the original barometer came with a leather case, allowing it to be safely transported during journeys. It is quite uncommon to find a Bourdon barometer used as a travelers’ barometer.

On the back of the barometer, there is a small hatch. Bourdon barometers have a unique calibration method, unlike aneroids – a special key is required, which, when inserted into a centrally positioned port on the rear of the instrument, engages with the square base of the arbour. In doing so, a lever placed in the same plane and close to the arbour engages with the slipping drive pinion, allowing the arbour to be turned while the movement remains braked.