Dufy had been painting weather ever since his Fauve period: the clouds, rain, rainbows and sun so evocative of the climate of his native, constantly changing Normandy. Through his paintings they would become recognisable signs: a cloud is a looping ellipse, while the rain is those directional strokes we find in Hiroshige’s Hundred Views of Edo.

The rainbow, also to be found in his earlier works, is an optical phenomenon that makes the spectrum visible when sunlight meets rain: between 5 and 7 colours appear, ranging from red to violet. Over the sea that opens up the horizon, clouds, sun and rain allow this small rainbow to unfold. 

Visuel de la fresque (détail)

Linked to solar eruptions, the aurora borealis makes its “magical” appearance at the beginning of the painting, in yellow-pink colours above snowy mountains. Cavendish, one of the scholars in the frieze, was also interested in this phenomenon.  

Visuel de la fresque (détail)

Observation and explanation of the thunderstorm as the generator of lightning played their part in the birth of electricity. From the outset Dufy rendered this natural phenomenon with these white, yellow and blue streaks emerging from a black cloud on a pink sky. Other lightning bolts are at the centre of the composition between Zeus and the power station in Vitry-sur-Seine.

Visuel de la fresque (détail)

The sun was especially important for Dufy. Since his Fauvist days he had given up transcribing natural light, with local tone eliminated in favour of painterly light. Shadows no longer exist: “Thus each thing takes on its colour and its plane, not according to the lighting of nature but according to the order of the painting.” The questions of light and colour meet. 

Visuel de la fresque (détail)

After his trip to Sicily in 1926 and his experience of the glaring light there, he took a close interest in the painter Claude Lorrain, “his God”. Viewed frontally, the sun’s spectrum sets all the forms and objects ablaze at sunrise and sunset, as its colours spread and the whole takes on a fantastic dimension. The effect of this transposition is to play down the impact of the sun as perfected by Lorrain and Turner. This is the process at work in the right-hand part of the decor, where yellow and green sweep across the surface.

Visuel de la fresque (global, partie de droite)

This part can be read as an ode to creation and science, reminiscent of Lucretius’s De Rerum Natura, which Dufy read assiduously before embarking on this splendid project:

“Our starting point shall be this principle:

Nothing at all is ever born from nothing

By the gods’ will. Ah, but men’s minds are frightened

Because they see, on earth and in the heavens,

Many events whose causes are to them

Impossible to fix; so, they suppose,

The gods’ will is the reason. As for us,

Once we have seen that Nothing comes from nothing,

We shall perceive with greater clarity

What we are looking for, whence each thing comes,

How things are caused, and no “gods’ will” about it.”