pediment, in architecture, the triangular gable end on a building of classic type or a similar form used decoratively. It consists of the tympanum, or triangular wall surface, enclosed below by the horizontal cornice and above by the raking cornice, which follows the slope of the roof. In Greek architecture the pediment usually contained sculpture when used with the Doric order. In the Roman and Renaissance styles it was used also as a purely decorative motif, chiefly over doors and windows; the upper profile of the pediment was sometimes of segmental shape. In later Renaissance and baroque design the pediment often took on fantastic shapes, notably in the variants of the broken pediment, in which the two sides of the raking cornice do not join. The scrolled broken pediment was a favorite in American Colonial work, especially in doorways and over mantels.

In geology, any relatively flat surface of bedrock (exposed or lightly covered with soil or gravel) that occurs at the base of a mountain or as a plain having no associated mountain. Pediments are most conspicuous in basin-and-range-type desert areas throughout the world, but they also occur in humid areas. In the tropics, the surfaces tend to be covered with soil and obscured by vegetation. Many tropical river towns are situated on pediments, which offer easier building sites than the steep hillsides above or the river marshes below.

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A pediment is a classical architectural element consisting of the triangular section found above the horizontal structure (entablature), typically supported by columns. The gable end of the pediment is surrounded by the cornice moulding. The tympanum, or triangular area within the pediment, was often decorated with sculptures and reliefs demonstrating scenes of Greek and Roman mythology or allegorical figures it also consisted of many bright colours suitable to the nature of the building being adorned.

History

The pediment is found in classical Greek temples, renaissance, and neo-classical architecture. A prominent example is the Parthenon, where it served as a palette for beautiful, intricate sculptural detail, in the Roman Pantheon no such sculpture was intended. This Architectural elements was developed in the architecture of ancient Greece. In Ancient Rome, the Renaissance, and later architectural revivals, the pediment was used as a non-structural element over windows, doors and aedicules.

A variant is the "segmental" pediment, where the normal angular slope of the raking cornice is replaced by one in the form of a segment of a circle, in the manner of a depressed arch. Both traditional and segmental pediments have "broken" and "open" forms. In the broken pediment the raking cornice is left open at the apex. The open pediment is open along the base – often used in Georgian style architecture. A further variant is the "Swan-necked" pediment, where the raking cornice is in the form of two S-shaped brackets. The decorations in the tympanum can extend through these openings, enriched with "Alto-relievo" sculpture, "tondo" paintings, mirrors or windows. These forms were adopted in Mannerist architecture, and applied to furniture designed, or inspired, by Thomas Chippendale.

Significant pediments in the United States

• United States Capitol, Washington D.C.
• United States Supreme Court building, Washington D.C.
• National Archives Building, Washington D.C.
• Wisconsin State Capitol, Madison, Wisconsin
• Wayne County Building, Detroit, Michigan
• New York Stock Exchange Building, New York City
• San Francisco City Hall, San Francisco, California
• Missouri State Capitol, Jefferson City, Missouri
• Philadelphia Museum of Art, Philadelphia, Pennsylvania

In geology

In geology, a pediment is rock which slightly slopes upward along graded surfaces of rocks of various resistance. Gilbert (1877) first described pediments on the upturned edges of tilted beds of Henry Mountains in Utah. They slightly relate to the profile of graded streams.

See also

• Gable
• Temple (Greek)
• Temple (Roman)

References

• Dictionary of Ornament by Philippa Lewis & Gillian Darley (1986) NY: Pantheon
• Surface Processes and Land forms by Don J. Easterbrook (1999)NJ: Prentice-Hall, Inc

External links