• A story of design: more than nine decades of creativity and craftsmanship told in 4 chapters
  
• A tribute to mechanical ingenuity: a revolutionary ‘perpetual motion’ horological concept, where infinitesimal variations in the ambient air temperature provide 48 hours of autonomy
  
• An immersive experience: bringing together a collection of 19 different Atmos clocks and supported by archival materials, technical drawings as well as watchmaking demonstrations

During Milan Design Week this April, Jaeger-LeCoultre invites the public to discover ‘Living on Air’, an immersive exhibition that tells the remarkable story of the Atmos clock. Invented in 1928, with a unique mechanism that is driven by tiny changes in air temperature, the Atmos clock is a mechanical marvel and objet d’art in equal measure. An object of eternal fascination, the beauty of its mechanism and cabinet is more than equalled by its apparently magical way of working.

‘Living on Air’ is open to the public free of charge and will run from 8–13 April 2025 at Villa Mozart in the historic centre of Milan. During the exhibition, Jaeger-LeCoultre will unveil a new limited-edition Atmos clock that reflects the contemporary design values of Milan Design Week.

Founded in the Vallée de Joux in 1833, Jaeger-LeCoultre has been known for more than 100 years as the Watchmaker of Watchmakers^™. Blending innovation with centuries-old savoir-faire, linking the past to the future, the Maison is distinguished by the precision of its mechanisms and the unique marriage of technical ingenuity and aesthetic beauty that it brings to fine watchmaking.

As the guardian of the Atmos clock’s remarkable technology for more than 90 years, Jaeger-LeCoultre has continually worked on technical improvements and new developments and, since the 1970s, has invited a series of leading designers and masters of the artistic crafts to reinterpret this mechanical prodigy.

Bringing together an unprecedented collection of 19 different Atmos clocks spanning more than nine decades and supported by archival materials and technical drawings, as well as a watchmaker demonstrating how the mechanism works, ‘Living on Air’ tells the story of this extraordinary object in four chapters.

THE GENESIS: The (Seemingly) Impossible Dream traces mankind’s fascination with the idea of perpetual motion machines, with records dating back at least to first-century BC Alexandria, and reveals how, in 1928, Jean-Léon Reutter, a Swiss radiological engineer succeeded in incorporating the principle of perpetual motion into a prototype clock – apparently defying the laws of physics. On buying an early example of the clock – now known as Atmos 0 – Jacques-David LeCoultre realised that, despite the brilliance of the invention, the mechanism required exceptional watchmaking skill to make it viable and invited Reutter to join forces with the LeCoultre & Cie Manufacture to refine it for commercial production.

In the second chapter, THE MECHANISM: Inside the Atmos, visitors will discover how the Atmos clock comes closer to perpetual operation than any other mechanism yet created. The energy that drives the clock is supplied by normal fluctuations in air temperature. In live demonstrations, visitors can see how thermal energy is transformed into mechanical energy to power the movement. The secret lies in a hermetically sealed, gas-filled capsule, which is connected to the clock’s drive spring by a membrane. The slightest temperature variation changes the volume of the gas, causing the membrane to expand and contract – ‘breathing’ like the bellows of an accordion – and thus wind the spring.

THE DESIGN: Atmos, as an Objet d’Art celebrates the decorative crafts that elevate Atmos clocks into works of art, as well as highlighting how Jaeger-LeCoultre’s collaborations with leading contemporary designers have transformed the Atmos. Among the exhibits is a series of models created in collaboration with the renowned designer Marc Newson and exceptional examples of Atmos cabinets created by masters of wood marquetry and straw marquetry.

Because the Atmos system produces only a small amount of energy, its movement must consume as little as possible. In the chapter THE COMPLICATION: Beyond Timekeepings, visitors will discover how Jaeger-LeCoultre’s engineers solved the problem of adding functions to the clock without increasing energy consumption. They discovered that the ideal complications were those based on the long, slow cycles of the astronomical phenomena that lie at the origin of time measurement – such as the moon phases and seasons. Among the exhibits is the most complicated Atmos yet made, the Atmos Tellurium. Incorporating a tellurion – a three-dimensional mechanical mobile that precisely reproduces the true cycles of the Earth, Sun, and Moon – the clock also indicates the corresponding months and seasons with a zodiacal calendar, needing no adjustments until the year 2412 (excluding for seasonal changes).

More than nine decades after its invention the Atmos clock remains a unique and emotionally resonant keeper of time – a splendid homage to design and technical virtuosity that captivates with the beauty of its form, the serene movement of its balance wheel and the mystery of its workings.

‘Living on Air’ will run from 8–13 April 2025 at Villa Mozart (First Floor), via Mozart 9, Milan and is open from 11.00 to 19.00 (except on Wednesday 9, from 11.00 to 18.00). Visitors may register online in advance or on arrival at the exhibition.


Concurrently with ‘Living on Air’, Jaeger-LeCoultre is participating in a second event during the Milan Design Week, as the principal supporting partner of Homo Faber Fellowship. “Today’s Masters Meet Tomorrow’s Talents”, presented by the Michelangelo Foundation, is being held at the Casa degli Artisti in Brera. The exhibition features co-created objects designed and handcrafted by 23 duos – each comprising a master artisan and an emerging talent, or ‘fellow’, from a wide variety of countries – who were part of the second edition of Homo Faber Fellowship. Participating in Milan Design Week is a valuable opportunity for these duos to showcase their crafts.


Born in 1928, the Atmos is a clock like no other. An invention made possible by the extensive savoir-faire of the Jaeger-LeCoultre Manufacture’s watchmakers, the Atmos appears to defy the laws of physics, running for centuries without the need for any conventional energy source or rewinding. Instead, its mechanism is powered by normal, everyday fluctuations in air temperature; a variation of just one degree Celsius is sufficient to guarantee two days of running time. Since the 1930s, Jaeger-LeCoultre has harnessed the Manufacture’s watchmaking skills to continually make technical improvements, and its creative talents to enhance what has become a prized objet d’art. While the glass cube based on the Art Deco design of the Atmos II has become an instantly recognisable classic, Jaeger-LeCoultre has also collaborated with renowned designers and master artisans to create special editions of the Atmos.


Homo Faber Fellowship is a seven-month sponsored professional integration programme for master artisans and emerging talents, presented by the Michelangelo Foundation and supported by Jaeger-LeCoultre. The second edition began for the fellows in September 2024 with a one-month creative and entrepreneurial masterclass taught by ESSEC Business School and Passa Ao Futuro at the International University of Art in Venice. The participating fellows then spent six months in the workshops of their paired master artisans across Europe. During this time, the 23 duos were challenged to design and handcraft a co-creation inspired by Art Deco, a theme chosen by Jaeger-LeCoultre



Since 1833, driven by an unquenchable thirst for innovation and creativity, and inspired by the peaceful natural surroundings of its home in the Vallée de Joux, Jaeger-LeCoultre has been distinguished by its mastery of complications and the precision of its mechanisms. Known as the Watchmaker of Watchmakers^™, the Manufacture has expressed its relentlessly inventive spirit through the creation of more than 1,400 different calibres and the award of more than 430 patents. Harnessing 190 years of accumulated expertise, La Grande Maison’s watchmakers design, produce, finish and ornament the most advanced and precise mechanisms, blending passion with centuries-old savoir-faire, linking the past to the future, timeless but always up with the times. With 180 skills brought together under one roof, the Manufacture creates fine timepieces that combine technical ingenuity with aesthetic beauty and a distinctively understated sophistication.