How did a modernist landmark end up covered in plywood and graffiti?
In 1953, the Mercantile Library on Chestnut Street was considered the most important new building in America.

Cast your imagination back to 1953. The Korean War was winding down, Jonas Salk's polio vaccine was starting field trials, and modernist architects were experimenting with structures so light and transparent that the walls separating inside and out appeared to vanish. In Philadelphia, a 70-year-old architect named Sydney E. Martin borrowed the modernists' ideas to create a branch library that defied every convention of library design.
Until then, Philadelphia's local libraries were mostly neoclassical temples that followed Andrew Carnegie's template and presented a solid, majestic face to the street. After being asked to design a small branch on Chestnut Street for Center City's merchants and business community, Martin came up with a design that borrowed its moves from modern retailing.
Taking his inspiration from a Chestnut Street shoe store designed by architectural pioneers Oskar Stonorov and Louis Kahn, Martin produced a diaphanous glass jewel box, two stories tall and 35 feet wide. Large shop windows separated by the thinnest possible aluminum strips offered passersby views of the library's bookshelves and clusters of comfortable reading chairs. The design was such a sensation that it won the American Institute of Architects' gold medal in 1954 and was named one of the best buildings of the year by Architectural Forum magazine.
The Mercantile Library still stands at 1021 Chestnut St., but people are more apt to hurry past these days. The windows have been replaced with plywood, now heavily graffitied, and Martin's elegant metal frame looks as skeletal as the desperate panhandlers who take shelter in the doorway. Maybe it's better that people can't see inside anymore. Since the branch was shut down by the Free Library in 1989 because of concerns about asbestos contamination, the inviting, split-level interior has been completely gutted. Based on some accounts, the roof has caved in.
Despite its horrendous condition, the former Mercantile Library is too important to write off. It is now owned by Brickstone Realty, the developer that has done a heroic job of restoring historic treasures like the Hale Building on Chestnut Street and the Horn & Hardart on 11th Street. Given its simple form, the historically designated building should be a good candidate for renovation and reuse. An overbuild of several stories might offset the cost of rebuilding.
In his 1992 thesis on Center City's postwar architecture, historian Jeffrey L. Baumoel singled out the Mercantile Library as one of most daring modernist designs built in the city during the 1950s. The initial idea for the transparent facade came from Emerson Greenaway, head of the Free Library, who believed books should be treated as "merchandise" and put on public display. But Martin's execution went beyond his expectations.
To get the most out of the tiny site, Martin used a split-level layout inside. Visitors could descend a gracious open staircase to a lower level that opened onto a cozy garden, or head up to the mezzanine. A street-level lobby was furnished with plush, midcentury armchairs. An Inquirer reviewer, writing in 1954, marveled that the design "made using books seem natural."
Until receiving the library commission, Martin had never worked in the modernist style. But after teaming up with two much younger designers in the early '50s to form Martin, Stewart & Noble, he moved in that direction. At the time, Philadelphia's modernists were still a cautious bunch, producing hybrid buildings that followed the modernists' straight lines but rendered them in traditional brick and stone. Except for the granite piers bookending the library, the Mercantile Library was masonry-free.
Just a few months after Martin's library opened, it was eclipsed by an even bolder glass-and-aluminum design, the Manufacturers Trust Co. Building on Manhattan's Fifth Avenue. Although the New York building is now considered the pioneer of transparent commercial buildings, it's worth remembering that the Mercantile Library paved the way.