Photograph by Alastair Phillip Wiper, 2012,
with thanks to RIBA

This is the Mont-Louis Solar Furnace at Odeillo, Eastern Pyrenees. I am at a loss how to describe it actually. So beautiful. So functional. 
      Its designer is the French engineer Félix Trombe. He built it out of 9600 mirrors, placing them so that the sun's energy focused onto a platform about the size of a frying pan.
      Temperatures could reach 3,500 degrees C, allowing scientists and fellow engineers to use it as a materials testing lab.

Since COVID-19, I have started judging the value of city life according to how near I am to one of these. Think of the root system as the mind; think of the stem as the neck; think of the crown as the lung.