Entasis
Entasis: A line between A and C attached to the column is slightly curved outwards. This creates the impression of bulging in the lower third. The taper does not seem to start until above B.
Entasis ( Greek ἔντασις "tension") denotes the swelling or bulging of the shaft of a column . It is caused by a circular arc-shaped, non-linear tapering of the column diameter, which accelerates upwards above all from the lower third point or the middle of the shaft.
Like the curvature of the stylobate and the architrave as well as the inclination of the columns and walls, the entasis, according to Vitruvius (III 3, 13), serves to refine the building's appearance; it should be more “pleasing” to the eye.
Statics
In the case of massive columns, from a static point of view, the base of the column should have the largest diameter, since this is where the compressive stress is highest. In contrast, in the case of slender columns, the center of the column should have the largest diameter, since this is where the risk of buckling is greatest. The entasis can be seen as a combination of these two design principles, i.e. H. the diameter is greatest at the base of the column and decreases slowly to the center of the column, but then more and more rapidly. However , it is probably not known whether static considerations played a role in addition to aesthetics in classic buildings .
history
prehistory
Some of the early large menhirs in Brittany (e.g. menhir from Champ Dolent , menhir from Kerloas ) show conspicuous thickenings at a height of approx. 3 to 4 m. The reasons for this are unclear, but aesthetic considerations may have played a role.
Antiquity
Entasis occurs primarily in temples of the Archaic and Classical periods , both of the Doric and Ionic order . It is most pronounced in the Great Greek temples of southern Italy and Sicily .
There is usually no evidence of entasis in Hellenistic buildings . But it occurs occasionally and can now also affect columns of the Corinthian order . Hermogenes considered at the beginning of the 2nd century BC. The entasis on the pillars of his temple buildings. Ancient architectural drawings of the Entasis design have been preserved on the Didymaion near Miletus .
In the Roman architecture of the imperial era, the entasis was usually no longer designed as a uniform curve, rather the shaft was divided into two straight tapering areas and only the joint area was rounded off.
Middle Ages and Renaissance
In the Middle Ages, and even in Renaissance architecture , columns with entasis are extremely rare. In the south of France there are monolithic columns with entasis in the early Romanesque upper church of the Abbey of Saint-Martin du Canigou .
Leon Battista Alberti describes how an entasis is created around the middle of the 15th century, Andrea Palladio explains a simpler method.
Doric columns of the Temple of Athena in Paestum , Italy
Upper church of the Abbey of Saint-Martin du Canigou, columns with entasis
literature
- Walter Thomä: The swelling of the column (entasis) among architectural theorists up to the 18th century. Century. Dresden 1915
- Lothar Haselberger (Ed.): Appearance and Essence. Refinements of Classical Architecture: Curvature . University Museum, University of Pennsylvania, Philadelphia 1999 ( Museum monographs (Philadelphia) . Vol. 107).
- Dieter Mertens : On the origin of the entasis of Greek columns. In: Hermann Büsing - Friedrich Hiller (Ed.): Bathron. Contributions to architecture and related arts for Heinrich Drerup on his 80th birthday . SDV Saarbrücker Druckerei und Verlag, Saarbrücken 1988, pp. 307-318 ( Saarbrücker Studies on Archeology and Ancient History . Volume 3).
- Burkhardt Wesenberg : The theory of entasis. In: Archäologischer Anzeiger 1999, pp. 481–492
- Entasis. In: Johann Heinrich Zedler : Large complete universal lexicon of all sciences and arts . Volume 8, Leipzig 1734, column 1264.