File:Plan.tourelle.XIIe.siecle.png

...Dès le XII^e siècle, les constructeurs portaient souvent des tourelles contenant des escaliers ou servant d'échauguettes sur des contre-forts d'angles; mais la circonférence de ces tourelles débordant sur une partie de leur surface, les saillies de ces contre-forts, ainsi que l'indique le plan (19), il restait des triangles A qu'il fallait soutenir par des encorbellements dont l'assise inférieure, au moins, était taillée en forme de cul-de-lampe..

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.
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