Barometers Realm

The case is fitted with a hinged lid, which locks at the base with two metal latches. The lid lifts smoothly, yet you can feel its weight and strength, providing a tactile experience that enhances the interaction with the instrument. A sturdy, cold iron handle adds a touch of industrial style, which perfectly complements the refined wooden foundation.

One of the most striking elements of this barograph is the glass embedded in the front and sides of the lid. It reveals the inner workings of the mechanism, allowing the viewer to observe each movement of the recording lever. This design creates an almost theatrical effect, as if inviting the audience into the intimate space where mechanics and nature converge. A mirror on the back wall inside the case enhances the visual perception, doubling the image and playing with light, adding a magical effect to the barograph. Light passing through the glass reflects in the mirror, as if highlighting each stroke of the mechanism's work.

At the heart of this device is a heavy brass drum, 95 millimeters tall, firmly holding the paper chart with a securing clamp. This drum appears to be the foundation of the entire structure—its weight and golden hue give the instrument a sense of importance and undeniable precision. Against this backdrop, the recording lever, light and delicate with its graceful pen tip, seems almost weightless. Each movement it makes is a recorded trace of the atmosphere, frozen in time. A small brass lever on the front of the device allows the user to lock the recording mechanism, adding an element of control to the process—another example of thoughtful functionality, executed with artistic flair.

The barograph is equipped with a miniature mercury thermometer, crafted from ivory. Its centigrade scale is precise and neat, and the material of the thermometer lends the instrument a sense of exclusivity and refined taste. Completing the composition is an ivory plate, engraved with standard weather indicators in French, like quiet whispers from the past, reminding us of predictions based on long-term weather observations.

On the brass base is the "RF" logo (Richard Frères) and the inscription "Paris Breveté SGDG," indicating that the barograph was likely made in France. Breveté SGDG is a type of French patent—“Patent Without Government Guarantee.” Also engraved on the brass base, hidden under the drum, is the inscription: "RICHARD FRÈRES CONSTRUCTEURS BREVETES PARIS," meaning "Richard Frères Patented Manufacturer." On the back of the drum is the phrase: "8 JOURS ECHAPT CYLINDRE," meaning an eight-day cylinder movement. The bottom surface of the barograph case is lined with green velvet, protecting it from scratches when moved.

The heart of the barograph consists of 8 aneroid capsules, with corrugated shells like those in standard aneroids, supported by spring plates inside to prevent the capsule walls from collapsing. These springs, made of steel, prevent the walls of the aneroid chamber from caving in. The capsules are stacked vertically, one screwed into the other. The base of the column is fixed, while the top end rises and falls with every change in atmospheric pressure, reflecting the combined deflections of the individual capsule shells. In this way, any changes in the walls of the aneroid capsules are immediately transmitted to the lever with the recording pen.

Temperature compensation is achieved by leaving just the right amount of air in one of the capsules, determined experimentally during the instrument's construction. This ensures that when temperatures rise, the barograph’s tendency to underestimate readings due to weakened springs and the expansion of levers and other parts is counterbalanced by the increased air pressure within the capsule.