Merlon

A merlon is the solid upright section of a battlement or crenellated parapet in medieval architecture or fortifications. Merlons are sometimes pierced by narrow, vertical embrasures or slits designed for observation and fire. The space between two merlons is called a crenel, and a succession of merlons and crenels is a crenellation. Crenels designed in later eras, for use by cannons, were also called embrasures.

The word comes from the French language, adapted from the Italian merlone, possibly a shortened form of mergola, connected with Latin mergae (pitchfork), or from a diminutive moerulus, from murus or moerus (a wall). An alternative etymology suggests that the medieval Latin merulus (mentioned from the end of the 10th century) functioned as a diminutive of Latin merle, expressing an image of blackbirds sitting on a wall.

As an essential part of battlements, merlons were used in fortifications for millennia. The best-known examples appear on medieval buildings, where battlements, though defensive, could be attractively formed, thus having a secondary decorative purpose. Some (especially later) buildings have false "decorative battlements". The two most notable European variants in Middle Ages merlons shape were the Ghibelline and the Guelph merlon: the former ended in the upper part with a swallow-tailed form, while the latter term indicates the normal rectangular shape merlons (wimperg).

Other shapes include: three-pointed, quatrefoil, shielded, flower-like, rounded (typical of Islamic and African world), pyramidal, etc., depending either from the type of attacks expected or aesthetic considerations.

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