Inside Conservation
By Lucy Commoner, with Perry Choe, Kira Eng-Wilmot, and Annie Hall
HISTORY OF CONSERVATION AT COOPER HEWITT
Cooper Hewitt has a long and deep history of caring for its collection. Although there were no conservators on staff when the museum was in its original home at the Cooper Union, the curators were active participants in the preservation of the collection. Following the model of the Victoria and Albert Museum in London — one of the institutions that inspired the founding Hewitt sisters to create Cooper Hewitt in 1897 — the curators served both as interpreters and “keepers” of the collection, responsible for its accessibility, organization, and safe storage.
After joining the Smithsonian in 1967, and opening its doors in the mansion in 1976, Cooper Hewitt officially added its first staff conservator: Lucy Commoner, Textile Conservator. Soon after, paper conservator Konstanze Bachmann joined, and decades later — through an endowment challenge grant from The Andrew W. Mellon Foundation — the museum hired an objects conservator, Annie Hall.
Today, the museum has four staff conservators who are responsible for the preservation of the collection, operating out of four conservation laboratories located on the museum’s New York City campus and at an off-site research and storage center. The team includes: Lucy Commoner, Head of Conservation; Perry Choe, Senior Paper Conservator; Kira Eng-Wilmot, Senior Textile Conservator; and Annie Hall, Senior Objects Conservator.
WHAT DO CONSERVATORS DO?
Cooper Hewitt conservators support the curatorial division as well as the exhibitions and registrar departments to preserve not only the museum’s collection, but also loaned objects while on exhibition and in storage. The conservators analyze and treat objects to maximize their longevity, aesthetic and structural integrity, and technical interpretation through a fascinating combination of science and art.
COOPER HEWITT’S RENOVATION AND REINSTALLATION
The range of responsibilities of the conservation department is wide, and at no time was that more evident than during the planning and execution of the museum’s renovation and reinstallation. As the first step in this multiphase project, Cooper Hewitt built a new off-site research and storage center that encompasses storage rooms, a conservation laboratory, a photography studio for digitizing the collection, offices, and a curatorial study room. Working with Smithsonian architects, engineers, and security staff, the conservators contributed their expertise to the design of the center, the materials used in its construction, the layout of the storage rooms, and the design and equipping of the conservation laboratory. Once the new off-site facility was complete, the conservators and registrars moved the majority of the collection from the Carnegie Mansion to off-site storage so that the renovation project could begin.
REDESIGNING AND RENOVATING THE CARNEGIE MANSION
The staff conservators were involved in not only advising on the building restoration aspects of the renovation of the historic mansion, but also creating an appropriate preservation environment within the building, which functions as the primary container for the collection. Many of the same building materials and finishes that contribute to interior pollution and an unhealthy environment for people can also have detrimental effects on art objects, although objects are often more sensitive to damage from pollutants than the human body. During the renovation process, the conservators approved all the materials that were used for any new interior construction and finishes in the building, and worked on establishing optimum temperature and relative humidity levels in the building for preserving collections, while, at the same time, protecting the historic building and maintaining comfort levels for visitors.
NEW EXHIBITION CASES
Once the building itself meets conservation standards, exhibition cases serve as a secondary container and level of protection from dust and particulates in the air as well as a buffer against any unexpected environmental changes within the building. With a relatively small volume of air in the cases, it is essential to control all the materials within the case to ensure that they are archival quality, have stable longevity, and will not produce volatile corrosive chemicals, such as acids and formaldehyde.
The conservators worked with designers Diller Scofidio + Renfro and case manufacturer Goppion to select conservation-approved materials and finishes. The conservators and exhibition staff explored new approaches for the permanent cases that would facilitate the installation of objects, ensure their support and physical protection, and provide the sustainable flexibility desired by the curatorial staff.
MAINTAINING THE NEW PRESERVATION ENVIRONMENT
The conservators’ basic areas of management in the galleries are light, environment (temperature and relative humidity), and particulates (dust). All of the windows in the mansion are fitted with screens and filtering film to reduce the level of light in the galleries and to block the damaging ultra-violet portion of incoming daylight. The second source of light in the galleries is the new, computer-controlled overhead lighting system. For the first time, the museum is using energy-efficient LED (Light Emitting Diode) fixtures as the primary source of interior lighting. The conservators worked with the exhibitions department and lighting designers from Renfro Design Group to select and test the fixtures and to specify exact lighting intensity levels for each object on view.
Cooper Hewitt conservators have established a controlled range of temperature and relative humidity measurements that relate to different seasons of the year and to the requirements of the historic building. The same conditions are maintained in all of the museum’s facilities so that objects can be moved from one location to another without a change in environmental conditions.
Crucial to the maintenance of a stable environment is accurate monitoring. The museum received a generous grant from the Smithsonian Collections Care Initiative to support the purchase of environmental meters and wireless data-logging equipment to measure environmental and light level conditions in the galleries, storage, and collection work spaces throughout the renovated museum.
Air-borne particulates can have an abrasive effect on exposed objects as well as attracting insects and holding moisture. Dust in the museum environment comes from many sources, including visitors’ clothing and carpets in the museum. Exterior sources of dust and pollutants are reduced through special filters within the HVAC (Heating Ventilating and Air Conditioning) system. Interior sources of dust are controlled through good housekeeping, which involves exhibitions, maintenance, and conservation staff working together to clean platforms, cases, and exposed objects on display. Although not the most glamorous of the conservators’ responsibilities, it is vitally important — in terms of both aesthetics and preservation — and gives the conservators the opportunity to carefully observe objects on display for any signs of damage.
It is this close observation and technical understanding of individual objects that is at the core of what conservators can contribute to any museum project that impacts the collection. Cooper Hewitt’s conservators were very gratified to have been such an integral part of this once-in-a-career opportunity to renovate and reimagine the museum for the future.
CONSERVATION AT WORK
The reinstallation of the museum included nearly 500 objects from the museum’s permanent collection, each of which required its own level of analysis, treatment, and installation by the conservators.
ANALYSIS
TEXTILE CONSERVATION — FIBER IDENTIFICATION IN THE NEW CONSERVATION LAB
Conservators use various methods of scientific analysis to learn more about the objects in their care. Analysis contributes to the examination of an object’s condition over time and informs decisions regarding each object’s treatment and storage, while providing technical information that enhances the curatorial understanding of an object.
One mode of inquiry frequently used for the Cooper Hewitt textile collection is microscopy. A stereo microscope (which offers 5 to 50 times magnification) can be used to look closely at the surface of a textile to determine weave structure and technique as well as to examine damage more closely. Polarizing light micros- copy (which provides 100 to 500 times magnification) is employed to identify the type of fibers used to construct the textile, which come from a variety of natural and synthetic sources. Cellulose- based vegetable fibers produced from plants include bast or stem fibers (such as flax, jute, hemp); seed fibers (such as cotton); and leaf fibers (such as sisal and abaca). Animal fibers are protein-based and include silk and the wool or hair of various animals. Examples of synthetic fibers are polyesters, spandex, and nylon. Every fiber type has a unique set of morphological qualities that can be identified under polarizing light microscopy. The medium of each of the textiles on exhibition has been corroborated through microscopy in tandem with the curators’ research, so that a thorough understanding of the object can be communicated to Cooper Hewitt’s visitors.
TREATMENT
OBJECTS CONSERVATION — THE CONSERVATION TREATMENT OF A BIRDCAGE
One of the objects treated for installation in the new galleries is an eighteenth-century birdcage from China. Primarily produced in the era of Ch’ien Lung, a Chinese ruler known for his artistic sensibility, this birdcage marries beauty and function. Many of the components of the birdcage are ivory, including the cage bars, bowls and feeders, perches, ornaments, and a long, elegant worm feeder. Other materials include bone, metal, jade, amber, enamel, porcelain, carved, lacquered, and inlaid wood, and kingfisher feathers set in gilt metal. There is also a hanging chain of amethyst, jade beads and jade rings.
In preparation for display, a treatment strategy was developed in consultation with the curator, which included cleaning all of the elements and replacing missing parts — such as two of the ivory cage bars — which were replicated with bars made from cast epoxy and painted to match. In keeping with the nature of the birdcage, the intent was to restore the aesthetic integrity of the piece while also providing the correct structural support for stability. Over forty individual pieces were removed from the birdcage for treatment and then separately packed for shipment from the off-site facility to the museum. This required scrupulous documentation notes and reference images to ensure accurate reassembly of the birdcage, the conservator’s final task. The display requirements also included working with the design team to find solutions to support the cage from below, hanging the cord safely from above without taking excessive weight, in order to give the cage the illusion of floating in midair.
INSTALLATION
PAPER CONSERVATION — A NEW APPROACH TO THE DISPLAY OF WORKS ON PAPER
For the second-floor galleries, which are dedicated to the display of objects from the museum’s permanent collection, the innovative and versatile design of the new exhibition cases allows for a fresh approach to the presentation of collection objects. The new system features pinnable fabric-covered walls that allow for the easy and safe vertical installation of flat objects; a custom bracket for displaying rolled textiles and wall-coverings; and a flexible system of shelves and tables for showcasing 3D objects.
Due to the flexibility of the case design, objects of varied formats (rolled, flat, and 3D) can be shown together within the same protected environment. The conservators and exhibition staff developed the concept of pinnable vertical panels for the case interiors, specifying a thick, high-density polyethylene foam covered with a thinner layer of soft, polyester foam and finally wrapped in the display fabric. All of these materials were tested by conservation for their chemical stability through a type of accelerated aging procedure called the Oddy test.
With the new system, the conservator mounts flat and rolled objects in situ as opposed to framing works before the installation period. Flat works in mats no longer need to be framed, and rolled objects are no longer mounted in acrylic box frames offering improved sustainability, cost-effectiveness, and efficiency.
TREATMENT
OBJECTS CONSERVATION — THE CONSERVATION TREATMENT OF A STAIRCASE MODEL
A complex object that presented conservation challenges for the reopening was this staircase model given to the museum in 2007 by Eugene V. and Clare E. Thaw. Made in France in the mid-to-late nineteenth century, the piece is constructed from carved, joined, turned, bent and planed oak. The conservator’s examination of the model revealed structural instability, largely due to old and new breaks from failing joints, and a range of aging repairs. The structural complexity of the curved double staircase design contributed to the near collapse of the second level balcony, which required the object to be supported while in storage.
The treatment to stabilize the object for exhibition involved a number of steps. Parts of the model were disassembled in order to access the areas to be treated and the wood was carefully cleaned. Old degraded repairs were removed and the model was reconstructed using archival fill materials and adhesives. The methods and materials were chosen to allow for future “retreat ability” so that any subsequent conservation action would be achievable with minimal change to the original object.
This article first appeared in the Spring 2015 Design Journal, published by Cooper Hewitt, Smithsonian Design Museum.
