Versailles and the history of the skylight

Anyone interested in architecture’s environmental history will find it puzzling that there is little written about the history of daylighting, or the history of the skylight. Who invented the modern skylight? We don’t know! It probably developed in France in the 18th-century.

The Palace of Versailles helps to define some boundaries for this question. The famous Galerie des Glaces (Hall of Mirrors) has tall windows but not skylights⁠—the skylight did not yet exist. Therefore this room exemplifies state-of-the-art side-lighting techniques for its time. Each tall window on the left of the image below (facing WNW) is matched by a mirror on the right; this works fairly well to distribute light throughout the space. The chandeliers help.

About 150 years later, the Galerie des Batailles (Hall of Wars) was constructed; second image below. By this time, the modern skylight had been introduced.* The skylight was a significant advance, because top-lighting techniques provide better illumination than side-lighting.

The two rooms provide an excellent compare-and-contrast for daylighting designers because they are about the same size and shape, and only a few hundred feet apart. Clearly the later room is brighter and lit evenly.** For history students, this is also a fine compare-and-contrast of the Baroque and Neo-Classical styles.

*An earlier skylight of note is found at the 1784 "La colonne brisée" at Désert de Retz, just a few miles from Versailles. Thomas Jefferson was “enchanted” by this structure, and he built the first skylights in America at Monticello after 1796.
**These rooms are contrasted in David Lee Smith's Environmental Issues for Architecture, though the time interval isn’t mentioned.