Introduction
Anyone who has ever walked through historic houses and large public
buildings, visited an art gallery, picked up a picture frame in
an antique shop, or even ridden on an old carousel has been close
to composition ornament, but has probably not known what
it was or how it was made. This is not surprising, since composition
or "compo" was conceived as a substitute for more laboriously
produced ornamental plaster and carved wood and stone, so was
intended to fool the eye of the viewer. The confusion
has been heightened over time by makers who claimed to be the
sole possessors of secret recipes and by the variety of names
and misnomers associated with the material, including plaster,
French stucco, and Swedish putty, to name a few.
Many natural or man-made materials can be made soft or "plastic"
by the application of heat and are called "thermoplastics."
Composition is a thermoplastic material used to create sculptural
relief. It is soft and pliable when pressed into molds; becomes
firm and flexible as it cools; and is hard and rigid when fully
dry. Typically formulated with chalk, resins, glue, and linseed
oil, this combination of materials gives compo its familiar light-to-dark
brown color. It is the only one of the so-called thermoplastic
materials to be used extensively in architectural decoration because
of its low cost.
Generally adhered to wood, historic composition ornament is most
often found decorating flat surfaces such as interior cornice
and chair rail moldings, door and window surrounds, mantelpieces,
wainscot paneling, and staircases-indeed, anywhere that building
designers and owners wanted to delight and impress the visitor,
but stay within a budget. While composition was cheaper than carved
ornament, it was still meticulously hand made and applied; thus,
it was more often used in "high style" interiors. But
the types of structures historically decorated with composition
ornament were more democratic, encompassing residential, commercial,
and institutional buildings, and even including specialty applications
such as the social saloon of a steamship.
With proper understanding of the material, historic composition
ornament may be successfully cleaned, repaired, or replaced in
sections. Unfortunately, because composition is often misidentified
as plaster, stucco, or carved wood, the use of inappropriate methods
for removing paint is a major cause of its loss.
The purpose of this Brief is to to assist historic property owners, managers,
architects, craftsmen, and preservationists
in identifying existing composition ornament, determining the
extent of repair and replacement needed and, finally, selecting
the most sensitive, non-destructive method of treating it.