Post did not, however, abandon the romantic arch or the triple window motif by any means, for he did incorporate both details into his design of the New York Produce Exchange. In October 1880, he was named the winner of an invited competition to design the building for a site adjacent to the Bowling Green at 2 Broadway. Among the architects invited for the competition had been Charles B. Atwood, Leopold Eidlitz, Richard Upjohn, and E. Townsend Mix (the Milwaukee architect who had designed the Mitchell and Chamber of Commerce Buildings), who took second place. It is interesting to note that while Post was involved in the design of two of New York’s larger buildings at the same time, he was still experimenting with both the formal and the rational alternatives to facade composition that were then in fashion. While he had refined the use of multistory piers to impart a vertical accent to the elevations of the Mills Building, Post was incorporating superimposed multistory arcades to organize the horizontal elevation of the Produce Exchange. This was probably due to the different proportions of the Produce Exchange that were much longer (300′ x 150′) and, therefore, more horizontal than those of the Mills Building. One cannot ignore the symbolic image, however, that the building exudes recalling the Renaissance palazzos of Florence, the “trading” capitol of Italy. He incorporated a 225′ tall tower in the Produce Exchange that lent a counterbalancing vertical force to the building’s horizontal composition as well as a civic presence in New York’s urban landscape, once again seemingly recalling the towers of Florence’s Palazzo Vecchio and Siena’s Palazzo Pubblico.
Although his winning design included a mansard roof not unlike his original design for the Mills Building, the later addition of another floor allowed him to reconsider and he opted for the palazzo box. Historians have likened Post’s final design of strong, horizontal layers to each of the master palazzos of Medici-Ricardi, Strozzi, and Rome’s Farnese.
None of these palazzos, however, incorporated the motif of stacked arcades in a geometric progression. I have reviewed Post’s early experiments during the early 1870s with arcaded elevations, but none of these ever used a sequence of arcaded spacings. For Post’s inspiration we must credit Richard Morris Hunt in his early scheme for the New York Tribune Building.
I chose Hunt’s scheme over those by Lienau and Richardson (see Section 5.9) because Hunt did not use an A-B-A rhythm in his arcades; i.e., a major-minor rhythm between the primary piers and the intermediate piers. More on this later.
Post broke the elevation into four horizontal layers that expressed the building’s internal organization. A one-story base of square-headed shops was surmounted by two layers of arcades: the lower layer corresponding to the 64′ high Exchange Room at the second floor and the upper one to the office floors above it. Colossal pilasters at the corners were used to frame each layer, as well as to provide the symbolic buttressing of the end thrusts of the arcades.
The arcade that surrounded the Exchange Hall set the primary structural bay and was detailed to contain four layers of triple windows. The upper arcade doubled this rhythm with two arches over each primary arch below and contained two floors of offices. The corner pilasters grouped this arcade with an attic of square-headed windows that again doubled the spacing, so that four windows were located within the primary bay. Post had arranged the openings in the red brick and terra-cotta exterior in a increasing geometric progression of 1:2:4 while the number of floors had a vertical rhythm of 4:2:1. An arcaded cornice enclosing the top floor of offices capped the composition. The genius I see in this portion of the façade is that the smaller windows relate directly to the fact that the offices on this floor were smaller than those in the two lower floors (see below for this reason). In my opinion, this building (and its architect) has never received the recognition its quality demands.
Unlike Lienau and Richardson, who set the primary rhythm or “measures” in their layered arcades by carrying the major piers up, into the upper arcades, and then articulated the hierarchical rhythm in the smaller, upper arcades by modulating the thickness of the piers with respect to their overall position in the geometric order (as Richardson did in the Cheney Block), Post treated each arcade as a layer unto itself and made no differentiation in the piers’ thickness within an arcade layer. This resulted in an unrelenting staccato across the 300’ long face of the building within the confines of the corner colossal piers that gave the elevation a strong, unmistakable horizontal reading, that was complemented by a monochromatic color palette of cherry red brick and matching terra cotta.
Faced with a program that required a very large (215’ long x 134′ wide), skylighted trading room with a ceiling height that varied in height from 45′ to 64,’ in addition to the requirement to provide 300 private offices for the brokers and rental income, Post revisited his original hollow-donut plan scheme for the Mills Building and arrived at a solution not unlike his design for the Equitable Building.
He placed the four floors of office space above the trading room and lined the perimeter of the large site with the cellular offices (the lower two floors contained larger offices that were single-loaded while the offices in the upper two floors were smaller and, therefore, could be double-loaded), thus creating an exterior lightwell in the center that not only lit and ventilated the inner tier of offices, but also allowed the placement of a skylight over the center of the trading floor to illuminate it as well.
The requirement for a column-free interior in the trading room forced Post to use long-span wrought-iron trusses. Instead of supporting these directly on the large cast iron columns that supported the four floors of offices above, however, Post extended a cantilever from each column to move the support end of the truss a distance away from the column. This allowed him to create a range of clerestory windows under the truss that would provide daylight for the Exchange Hall that was pulled away from the windows of the offices that lined the light court, thereby avoiding any conflict between either set of windows. This detail also provided a space for maintenance men working on the skylight, as well as provided space for snow to accumulate without piling up against the windows of the adjacent offices. Using a similar detail to what is thought he had used in the Equitable Building’s lightcourt exterior walls, he designed the four stories of exterior walls ringing the lightcourt as an iron skeleton frame that supported its exterior brick curtain walls.
He expressed the iron structure in the design of these elevations by articulating the rectilinear framework of columns and beams by covering them with a cast iron panel, a detail similar to how Bogardus had protected the iron columns in the Tatham Bros. shot tower of 1856. By simply infilling the voids either with double-hung windows or with a brick panel, he had created one of the earliest, if not the first, truly modern curtain-walled exterior elevations based on the expression of its construction and structure. Much later, at the 1894 A.I.A. Convention, Post would state:
“I built the tower of the Produce Exchange with a wrought and cast iron cage, filling in the panels with brickwork, but covering it on the outside with cast iron plates in the form of pilasters and stringpieces and cornices so that it could be painted as necessary… I have never enclosed a cage in solid mason work. I never dared to. I have always built the cage detached inside, anchoring the walls to it, so that in the case of corrosion, it could be painted and repaired.”
While there is only the one extant photograph of Post’s iron structure in the Equitable’s lightcourt walls, we know the Produce Exchange’s actual construction and final appearance from Post’s existing drawings and construction photographs.
There can be no argument about whether or not iron skeleton framing was first used by Post in these exterior walls of the Produce Exchange, for it is right there in the photograph, clear as daylight, for everyone to see. While James Bogardus can be credited as the inventor of the American iron skeleton frame, George Post deserves the credit as being the first post-Civil War architect in America to use the multistory iron skeleton frame in the exterior of a building. Again, I refer back to Daniel H. Burnham’s cryptic statement, “George Post was the father of the tall building in New York.” As there were no iron skeleton framed buildings in Chicago during the design and construction of the Produce Exchange, I repeat, Post deserves to be known not only as “the father of the skyscraper,” but also as “a pioneer of the iron skeleton frame” in the U.S.
FURTHER READING:
Landau, Sarah B. George B. Post, Architect. New York: Monacelli Press, 1998.
Landau, Sarah B., and Carl Condit. The Rise of the New York Skyscraper, 1865-1913. New Haven: Yale University Press, 1996.
(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)
The Architecture Professor 