Ogee

An ogee (/oʊˈdʒiː/ /ˈoʊdʒiː/) is an object, element, or curve—often seen in architecture and building trades—that has a serpentine- or extended S-shape (sigmoid).^[1]^: 218 Ogees consist of a "double curve", the combination of two semicircular curves or arcs that, as a result of a point of inflection from concave to convex or vice versa,^[1]^: 218 have ends of the overall curve that point in opposite directions (and have tangents that are approximately parallel).

First seen in textiles in the 12th century, the use of ogee elements—in particular, in the design of arches—has been said to characterise various Gothic and Gothic Revival architectural styles.^[1]^: 218 The shape has many such uses in architecture from those periods to the present day, including in the ogee arch in these architectural styles,^[1]^: 218 where two ogees oriented as mirror images compose the sides of the arch,^[3] and in decorative molding designs, where single ogees are common profiles (see opening image).^[1] The term is also used in marine construction.^{[citation needed]} The word was sometimes abbreviated as o-g as early as the 18th century,^[1]^: 218 and in millwork trades associated with building construction, ogee is still sometimes written similarly (e.g., as O.G.).^{[citation needed]}

Use in architecture

Ogee arch

In architecture, the principal use of the term is to describe an arch composed of two ogees, mirrored left-to-right and meeting at an apex.^[3] First seen in textiles in the 1100s CE, the use of ogee elements, and in particular in the design of arches, has been said to characterise Venetian Gothic and Gothic Revival architectural styles.^[1]^: 218.Ogee arches were also a feature of English Gothic architecture in the later thirteenth century.^[6]

Moulding

A building's surface detailing, inside and outside, often includes decorative moulding, and these often contain ogee-shaped profiles—consisting (from low to high) of a concave arc flowing into a convex arc, with vertical ends; if the lower curve is convex and higher one concave, this is known as a Roman ogee, although frequently the terms are used interchangeably and for a variety of other shapes. Alternative names for such a true Roman ogee moulding include cyma reversa and talon.^[7]

The ogee curve is an analogue of a "cyma curve", the difference being that a cyma, or "cyma recta", has horizontal rather than vertical ends. The cyma reversa form occurs in antiquity. For example, in ancient Persia, the Tomb of Cyrus featured the cyma reversa.^[8] The cyma reversa is also evident in ancient Greek architecture, and takes its name from the cymatium.^[9]^{[page needed]} The ogee and Roman ogee profiles are used in decorative moulding, often framed between mouldings with a square section.^{[citation needed]} As such, it is part of the standard classical decorative vocabulary, adopted from architrave and cornice mouldings of the Ionic order and Corinthian order.^{[citation needed]}

Ogees are also often used in building interiors, in trim carpentry, for capping a baseboard or plinth elements, as a crown moulding trim piece where a wall meets a ceiling, and in similar fashion, at the tops of pieces of case furniture.^{[citation needed]}

Other uses

Ogee is also a mathematical term, meaning an inflection point.^{[citation needed]} The term also gets used in steam locomotive design, referring to a specific shape of saddle tank on small shunting locomotives, such as the GER Class 209. In fluid mechanics, the term is used to refer to aerodynamic profiles that bear such shapes, e.g., as in the ogee profile of the Concorde supersonic aircraft.^{[citation needed]} As well, ogee curves are used to minimize water pressure on the downstream face of a dam spillway.^{[citation needed]}

In aesthetic facial surgery, the term is used to describe the malar or cheekbone prominence transitioning into the mid-cheek hollow.^{[according to whom?]} The aim of a mid-face rejuvenation is to restore the ogee curve and enhance the cheekbones, common parts of routine facelift surgery.^{[citation needed]}

Manufactured objects with the ogee description

Ogee is the name given to bubble-shaped chambers of pot stills that connects the swan neck to the still pot, in distillation apparatus, that allow distillate to expand, condense, and fall back into the still pot.^[10]

"Ogee washers" are heavy washers used in fasteners that have a large load-bearing surface; they are used in marine timber construction to prevent bolt heads or nuts from sinking into the face of timbers.^{[citation needed]} The term ogee is used to describe the ogee shape giving rise to radial symmetry around the centre of the washer.^{[citation needed]} Due to the size and shape of such washers, they are generally manufactured as a cast iron product (in accordance with ASTM A47 or A48).^{[citation needed]}

"Ogee clocks" were a common type of weight-driven 19th-century pendulum clock presented in a simplified Gothic style, with the original design attributed to Chauncey Jerome.^[11] Ogee clocks were typically made in the United States, as mantelpieces or to mount to a wall bracket,^{[citation needed]} and are one of the most commonly encountered varieties of American antique clocks.^{[citation needed]} The overall design was rectangular, with framing by moulding with an ogee-profile surrounding a central glass door with a painted scene below the clock face, a door that protected the clock face and pendulum.^{[citation needed]} Weights supported by pulleys fell inside the ogee moulding and so were hidden from view.^{[citation needed]}

References

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ As described in Lewis, Philippa & Darley, Gillian (1986). Dictionary of Ornament. New York: Pantheon Books. pp. 218, 222, 73, 97, and 116. ISBN 0-394-50931-5. Retrieved January 9, 2020. ogee. Combination of a concave and convex line, two recurve shapes, producing a serpentine shape, either as a moulding (an S form in cross section) or as an elaborated pointed arch. It is particularly characteristic of the Venetian Gothic Revival, Gothick and Gothic Revival styles, although ogee forms appeared in textiles from the 12th century. In the 18th century the word was sometimes written as o-g. A nodding ogee is an arch in which the head projects. See also syma recta/reversa; keel moulding. [p. 218] / ovolo. Convex moulding (usually a quarter of a circle in section)... [p. 222] / cavetto moulding or hollow chamfering (Latin, cavare, to hollow). One of the principal forms of moulding, a concave version of the ovolo moulding, usually a quarter of a circle in section. [p. 73] / cyma recta (Latin, cyma, wave). Important compound moulding, combining the ovolo and cavetto with the convex moulding below. In section the moulding is a double curve, concave above, convex below. Also known as ogee moulding. cyma reversa... [presenting concave below, convex above, p. 97]{{cite book}}: CS1 maint: multiple names: authors list (link)
^ The ogees are the nonlinear parts of the profile, only; the shaded area represents the side of the molding facing the wall of the building's room that is being decorated.
^ ^a ^b Davies, Nikolas; Jokiniemi, Erkki (2011). Architect's Illustrated Pocket Dictionary. Oxford, England: Architectural Press. p. 318. ISBN 9780080965376.
^ Pevsner, Nikolaus; Lloyd, David (1967). Hampshire and the Isle of Wight. The Buildings of England. Harmondsworth: Penguin Books. p. 505.
^ Honour, H. and J. Fleming, (2009) A World History of Art. 7th edn. London: Laurence King Publishing, p. 391. ISBN 9781856695848
^ Parker, John Henry (1850). A glossary of terms used in Grecian, Roman, Italian, and Gothic Architecture. Vol. 1. London: David Bogue. p. 159. OCLC 719426. Cyma recta…which is hollow in the upper part, and round in the lower; and Cyma reversa, (Talon…) which is hollow in the lower part and round in the upper.
^ Hogan, C. Michael (2008) Tomb of Cyrus, The Megalithic Portal, ed. A.^{[page needed]}
^ Dinsmoor, William Bell & Anderson, William James (1973) The Architecture of Ancient Greece: An Account of its Historic Development, Unknown location:Biblo & Tannen. ISBN 0-8196-0283-3.^{[page needed]}
^ Vriesekoop, Frank; Ostrowski, Dawid (2017). "Distillation Processes and Distillates". Post-Fermentation and -Distillation Technology. pp. 41–80. doi:10.1201/9781315155050-2. ISBN 978-1-315-15505-0.
^ Ly, Tran Duy (1997). New Haven Clocks & Watches. Arlington Press. ISBN 978-0-930163-75-4.^{[page needed]}