In September 2021, the Municipal Archives received the very welcome notice of grant funding from the National Park Service Save America’s Treasures (SAT) program to preserve the Brooklyn Bridge Drawings Collection. Established in 1998, the SAT celebrates the country’s premier cultural resources with grant support to preserve properties listed in the National Register of Historic Places and for projects involving collections that document significant places. The Institute for Museum and Library Services administers the SAT-funded projects.
Treating the Brooklyn Bridge Drawings, Phase One
On January 17, 2020, we introduced the Municipal Archives Conservation Unit’s latest project, “Conserving Central Park and Brooklyn Bridge Plans.” Before the Archives temporarily closed in mid-March, project conservators had devised some innovative protocols for treating the oversized plans (up to 36’ in length!) in these two iconic collections.
The project is funded by the New York State Library’s Conservation/Preservation Program. The goal is to perform the necessary treatments so that the drawings can be stabilized for improved storage, either rolled, or housed in new 7-foot long flat file drawers.
Conservator Clare Manias examines a 14-ft. Brooklyn Bridge drawing. NYC Municipal Archives.
Project conservators began with the oversize Brooklyn Bridge items. Drawings this large present a unique set of challenges. Routine treatments, transporting the drawings, photographic documentation, and use of available workspace all need to be approached differently. It became clear that we would need to think creatively to make the most efficient use of our time and workspace.
The constraints imposed by the size of the drawings means something as trivial as moving a drawing to the conservation laboratory requires three people. One person opens the doors and ensures the hallway is clear. The other two conservators load the drawings—usually 3 or 4 at a time—on a rigid foam core board which is carried by hand to the laboratory. The size of these drawings and the fact that they are currently housed in Mylar sleeves also makes them very heavy! In the laboratory they are placed on an extra-long table that can accommodate two drawings side by side. Two smaller tables that are on castors can also be pushed together to create another long table to accommodate some of the smaller drawings.
With these constraints in mind, we decided to batch our documentation photography, surface cleaning, and media testing as a “phase one” in treating the drawings. The basic “batch” process is as follows: we photograph a drawing, then while it is still in place on the table, we surface clean it, and test the solubility of the media. We also take notes on the condition of the drawing. Combining these tasks limits how often we need to transport the drawings to and from storage.
It is important to document the process of conservation treatments. Ethically, it is necessary for conservators to leave written and photographic documentation of the treatment that has been performed as a reference for future conservators. The photographic images taken during this process may be the only way for patrons to view the drawings, given their size and fragile state.
The size of these drawings required us to adopt innovative methods for the photography part of the project. Ordinarily, for small objects, a handheld camera or a camera on a copy-stand would suffice; however, these drawings are too long for that method. The majority of the drawings range between 6-to 15-feet in length and are about 2-to 3-feet wide. It is just not possible to capture the entirety of the drawing in one image, thus we shoot the recto and verso of each drawing in sections and later merge them together in Photoshop to create a panorama of the entire work. To successfully do this, we need to make sure that the images are all taken from the same angle, with the same settings, so that they will seamlessly align.
Conservator Sara Bone photographs an oversize Brooklyn Bridge drawing with the camera on the mono-stand, LED lights, and light reflection board. NYC Municipal Archives
The key piece of equipment for this type of photography is the mono-stand. The mono-stand allows the camera to be positioned about 9 feet above the floor, and the height can be adjusted, as needed. It is also on wheels, so it can easily be moved along each section as we take pictures. Blotters covering the table surface provide a clean, consistent background for the image and help to maintain contrast against the items we are photographing. The height of the camera on the mono-stand is adjusted based on the width of the drawing. A drawing with a smaller width means the camera can be closer to the object to have it fill out the frame. It is generally best to have the camera slightly zoomed in because when it is fully zoomed out it has a tendency to give a “fish-eye” effect, which makes stitching together the panorama more difficult.
With the camera positioned high up on the mono-stand, we need a stepladder to reach the shutter button! While there are some systems that sync the camera to a computer to remotely release the shutter, this is not possible with our setup.
Another vital piece of equipment are LED lights with softboxes that provide consistent diffuse light to ensure that the images are as accurate as possible. The overhead lights are turned off during photography because they have a warmer temperature light and do not provide even lighting. We rely primarily on the LED lights, although there is natural light that comes through the windows as well. A color bar is inserted into each of the photos so that in post-processing we can adjust the white balance and make sure the color information conveyed is accurate.
Because the drawings are placed on a table and the lights can only be positioned on one side of the table, the top edge of the drawings appear more in shadow. To aid in the way light reaches all areas of the image, we created our own light reflection board. A sheet of blotter was mounted to a rigid board and propped up on stands. When placed on the other side of the drawing on the table, this allows the light to bounce off the white blotter and reflect back onto the drawing. We move the light apparatus along with the mono-stand as we take the photographs at regular intervals, capturing every section of the drawings. Two people position the lights and reflection board while a third person is up on the stepladder taking the picture. Usually all three pairs of hands are needed to carefully flip the drawing over so the other side can be photographed.
In Photoshop, the images are adjusted for white balance and then cropped close to the borders of the drawing. The “Automate: Photomerge” function is used to automatically align the images into a panorama. Manual adjustments can then be made as needed.
Brooklyn Bridge drawing 4121-G, section. NYC Municipal Archives.
Following photography, with the drawing still out on the table, we begin the surface cleaning of both sides, using a soot sponge. The sponge lifts up the surface dirt without being too abrasive on the paper. Many drawings are so dirty that we see a dramatic difference as we clean! After surface cleaning the media is tested to see if it is water-soluble. Testing media is an important step because we need to check whether the ink is stable. We would like to wash as many of the drawings as possible to remove acids and other harmful byproducts in the paper. To test the inks and other media, we drop a small bead of water on an obscure section of the media to see whether the ink will bleed or if any lifts off when pressed with blotter.
Finally, we take notes on the condition of the drawing which completes phase one of treatment. Each drawing is then wrapped in acid-free buffered tissue and moved to temporary storage to await phase two, which will include more targeted treatments such as washing, mending, and lining. Using our batch treatment protocol we will photograph, surface clean, and media test the 78 Brooklyn Bridge drawings in an organized and efficient way.
We are looking forward to resuming the oversize drawings conservation project when the Archives re-opens. Look for updates in future blogs.
We’ll Be Back!
We’ll Be Back!
New York is a destination city. In 2019, more than 66 million visitors from the United States and around the world enjoyed sights and venues throughout the city with maybe only a “sold out” notice spoiling their good times. Preliminary numbers for 2020 looked like it would be another record-breaker. That is, until 8 p.m., March 22nd, when Governor Andrew Cuomo put New York State on “pause,” closing all but essential businesses and requiring residents to “shelter-in-place.” Overnight, the city’s entire $70-billion tourism industry evaporated.
Brooklyn Bridge and the lower Manhattan skyline, ca. 1987. The iconic towers of the Brooklyn Bridge, one of the greatest public-works achievements of the 19th Century, has attracted photographers since completion in 1883. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Times Square, ca. 1987. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
The current travel restrictions present an un-precedented and unique circumstance in New York City’s history. With the exception of a relatively short period after the attack on the World Trade Center in 2001, and the occasional blizzard or hurricane, visitors have enjoyed “the city that never sleeps,” without interruption.
New Yorkers are looking forward to the day when we will once again welcome friends and visitors to explore this great metropolis. In the meantime, we can ‘virtually’ visit some of the city’s most popular attractions as depicted in pictures commissioned by the New York Convention and Visitors Bureau in the mid-1980s. It is a small collection—only 52 transparencies—but their bright colors and iconic scenery showcase what the city has to offer. Although the pictures are not dated, based on signs and banners, it appears the bulk were taken in 1986 or 1987.
Fifth Avenue entrance, The Metropolitan Museum of Art, ca. 1987. The Museum’s entrance steps have long served as a welcome respite for visitors and a prime location for people watching. The Museum is celebrating its 150th birthday in 2020. New York Convention and Visitors Bureau. Collection. NYC Municipal Archives.
The New York Convention and Visitors Bureau created the photographs to illustrate their promotional materials. Formed in 1934 by merchants, hotel owners and other businesses to bring conventions to the city, the Bureau is a non-profit making entity. The Bureau and its companion organization, NYC & Company, are not city agencies, although they do receive budget support from tax-levy funds.
United Nations member flags welcome visitors to another popular city destination, ca. 1987. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
The bronze sculpture of Prometheus at Rockefeller Center is a can’t miss midtown attraction, ca. 1987. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Given the many enduring wonders of the city it would seem that the Bureau’s job would be easy. But there were times when promoting the city was a challenge. “Has New York's image unjustifiably soured, from Fun City to Crime City?” headlined a June 14, 1972, New York Times story about the Bureau’s launch of their annual “New York is a Summer Festival.” For the coronation of Ms. Bernadette Allen, the 19th-annual Summer Festival Queen that year, the Bureau hosted a gala event at one of the city’s premier tourist venues, the Empire State Building. They enlisted celebrities such as Duke Ellington and the “ageless” actress Gloria Swanson to preside over the festival. It is not entirely clear how Swanson’s remarks at the launch, as quoted in the Times, would help to promote tourism: “I chose to live in New York City in 1938 because I pay taxes here.” Perhaps the comment she added, “I’m the hostess with the mostest,” better served the cause.
The Twin Towers dominate the pre-9/11 Lower Manhattan nighttime skyline, ca. 1987. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Over the next several decades, the city experienced a renaissance and with it, tourism boomed. According to the Bureau, in 1977, more than 16 million tourists visited the city. By 1990, the figure climbed to 20 million, and surpassed 31 million by the end of the decade. After 9/11, tourism in the city gradually escalated up to 54 million in 2013. In 2019, the Bureau counted more than 66 million visitors—53.1 domestic travelers; and 13.5 arriving from overseas.
Taxis in Manhattan, ca. 1987. By the late 1980s, the Chevrolet Caprice had replaced the once-ubiquitous Checker Cab as the taxi of choice for fleet owners. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Antique auto in the Coney Island Boardwalk parade, ca. 1987. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Aqueduct Raceway in Queens, ca. 1987. The New York Convention and Visitors Bureau used their promotional materials to lure visitors to attractions outside Manhattan. New York Convention and Visitors Bureau Collection, NYC Municipal Archives.
Conserving Central Park and Brooklyn Bridge Plans
The New York State Library recently awarded a grant to the Municipal Archives Conservation Unit to perform much needed treatments on large-scale drawings and plans for Central Park and the Brooklyn Bridge.
Brooklyn Approach, East River Bridge, 1892. Wilhelm Hildenbrand, Brooklyn Bridge Collection, NYC Municipal Archives.
Lindsey Hobbs pasting out a sheet of Japanese tissue with wheat paste for lining a Brooklyn Bridge drawing.
These two icons of New York are among the most important public works achievements in the city’s history. Beyond the technological and design innovations, the bridge and park have become symbols of the city itself. The more than 200 drawings that are the subject of the grant exhibit the remarkable level of detail and artistry that went into the planning and construction of each structure.
The project focuses on the largest items in each collection, some of which are 34 feet long! Conservation staff are undertaking a variety of activities to assess and stabilize these delicate materials. These include mending and lining fragile drawings, stabilizing media, washing to remove harmful degradation products, reducing stains from mold and other sources on some of the most important drawings, as well as creating new housings for long-term storage.
The grant funding also supported the purchase of a Zeiss stereo microscope with a digital camera, and portable UV lights. This equipment allows conservation staff to analyze drawing media and supports, assess mold and other types of damage, and take high quality images of fine details, all of which will inform the treatment methods chosen. Additionally, the lab was able to purchase a large mono-stand for photographing oversized collections, both for documentation of the treatments performed as well as to provide another source of research access to these large, unwieldy objects.
Clare Manias and Sara Bone surface cleaning a Brooklyn Bridge drawing.
The Brooklyn Bridge and Central Park plans comprise some of the most treasured collections at the Archives. Dating from 1850 to 1934, the Central Park plans provide complete documentation during the critical stage of the park’s design and construction from 1850 to 1880. The collection includes renderings of everything from landmark structures like the Boathouse, Belvedere Castle, and Sheepfold to a three-level circulation pattern for people, horses, and vehicles. The oversized drawings included in the grant project detail the design of the Metropolitan Museum of Art and the Museum of Natural History, gates and entrances to the park, paths and walkways, drainage systems, and other elaborate details.
Conservators Clare Manias and Sara Bone prepare to photograph a Brooklyn Bridge drawing.
The Brooklyn Bridge collection documents the original construction and subsequent alterations of the 1,596-foot steel suspension bridge connecting Manhattan to Brooklyn. At the time of its completion in 1883, the bridge was the longest in the world and was an important technological achievement. The total 8,706 drawings in the Bridge collection span from 1867 to 1938. They were produced by architects and engineers who developed techniques for bridge construction that were unknown or considered unproven among their profession at that time. Many of the drawings in the collection are the work of the most celebrated American engineers and architects of the nineteenth century, such as John and Washington Roebling, George McNulty, and Wilhelm Hildebrand. The largest of these drawings is over 34 feet in length.
The drawings and plans in both the Central Park and Brooklyn Bridge collections have similar characteristics. They represent a variety of media (watercolor, graphite, inks, crayon, and photo-reproductive processes) and supports (tracing paper, watercolor paper, cloth-lined paper, and tracing cloth). Unfortunately, improper storage and handling over the decades prior to acquisition by the Archives has led to physical damage to varying degrees in the form of acidic and deteriorated supports, flaking media, iron gall ink damage, and tears and fractures.
Clare Manias and Sara Bone photographing a Brooklyn Bridge drawings in sections.
Assistant Architect Wilhelm Hildenbrand included some delightful details in his 1877 plans for the Brooklyn Bridge. Conservation staff spotted these two almost microscopic figures enjoying themselves on the bridge. A gentleman in a top hat appears to be serenading a lady holding a parasol.
One of the greatest challenges of treating these materials is simply moving them back and forth from and within the lab. Conservators Sara Bone, Clare Manias, and I have developed a workflow for carefully shifting and transporting the drawings using light, but sturdy, foam board to support their weight. We have also refined methods for photographing, cleaning, and performing various treatments on a much larger scale than we are generally accustomed to. Planning each move in advance, and of course teamwork, are key to safely maneuvering these massive and very delicate drawings.
The ultimate goal, as with most of the work we do in Conservation, is to make the oversized drawings safer to handle, more accessible to researchers and well-preserved for the future. As the project moves forward in the coming months, we will continue to learn a great deal about the collections and further refine our treatment methods. Given the many thousands of oversized maps and drawings in the Archives’ collections, these skills will no doubt be put to use again once this project is completed. Although challenging, the work will ensure the viability of these iconic materials for many generations to come.