File:Schema.lumiere.fenetre.png

...La lumière qui passe à travers une baie donnant dans un intérieur forme un cône ou une pyramide suivant la figure de la baie; c'est-à-dire qu'au lieu d'être divergents, les rayons lumineux sont convergents de l'extérieur à l'intérieur: ainsi (4), soit une baie abcd, l'extérieur étant en A, la lumière directe, pleine, formera la pyramide abcde, et tout ce qui ne sera pas compris dans cette pyramide ne recevra qu'une lumière diffuse ou de reflet...

This image comes from Dictionary of French Architecture from 11th to 16th Century (1856) by Eugène Viollet-le-Duc (1814-1879).

	This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 100 years or fewer. This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1929.
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.

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