Jenney, Home Insurance Building. Surviving fragment of the iron structure in the Museum of Science and Industry. Note the stub spandrel beam (at the left of the column) that the Field Committee chose to include in the fragment left for history. As this beam was located in only three of the eight floors that were skeleton-framed, the committee attempted to mislead future historians about the true nature of Jenney’s structure, (Author’s collection)

I have now shown you a litany of tall buildings in which some aspect of iron skeleton framing had been incorporated in their exteriors before Jenney first experimented with it in April 1884 for the Home Insurance Building. (There is no issue about interior iron skeleton framing in 1884, it was ubiquitous by then.)  The independent iron frame with a masonry curtain wall had been in service in the U.S. for some twenty-five years following Bogardus’ New York shot tower of 1855.   As far as I have been able to determine, George Post in New York had been the first American to use iron framing in an exterior wall since the urban conflagrations of Chicago and Boston in his detailing of the exterior lightcourts in the New York Produce Exchange (1880), and the Mills Building (1881), and just maybe even before the fires in in the Equitable Building (1867). These experiments were soon followed in Chicago by Root in his lightcourts for the Insurance Exchange, Phoenix Building, and also, of course, The Rookery (see an upcoming post).

So are we then looking for the first building whose exterior structure was solely iron framed?  If so, that leaves the Home Insurance Building out of the running because it still had two exterior loadbearing masonry party walls, in addition to the first two stories of its streetfronts having been solid masonry.  It will be a cautious step-by-step process in replacing the tried-and-true (and very stiff with regards to wind loads) bearing wall in the exterior of building with the iron frame.  The first all iron-framed tall building will be erected in 1888, and we’ll try to ascertain which building and architect/engineer deserves to be so credited when we get to that year.

Jenney, Home Insurance Building. Eighth floor plan. (Tallmadge, The Origin of the Skyscraper)

Admitting that the Home Insurance Building was neither the first skyscraper nor the first building completely framed in iron, then what “first-in-the-world” title is left for it to claim? (And why bother, other than for some civic boosterism on the part of Chicago?)  I think the best that one might argue is that it was the first use of iron skeleton framing in the exterior of a tall building in Chicago? (Remember, Post had already accomplished this in New York.)  Let’s examine this claim: that is, Jenney had used iron skeleton framing in the upper eight floors in the two street fronts.

Jenney, Home Insurance Building. Reconstruction of the structural detailing of the exterior piers. (Drawing by Deborah Cohen Heller and Maxwell Merriman)

From the evidence on record, we can conclude (please refer to my 1987 JSAH article for a more detailed explanation) from at least eight points that Jenney’s loosely-bolted, eight-story framework of masonry-stiffened cast iron columns and lintel pans was not entirely self-sufficient and independent of the masonry, and, therefore, does not qualify to even be called iron skeleton framing:

Jenney, Home Insurance Building. The exterior iron structure overlayed the building’s elevations, showing the lack of spandrel beams in Floors 5, 7, 8, and 10. (David Burwinkel)

-First, there were no spandrel beams at floors 5, 7, 8, and 10.  By definition, a frame is a rigid assembly of columns and beams at each floor (unless one is speaking about a megaframe, that in 1884 was in the distant future…);

Jenney, Home Insurance Building. Section and elevation of structural iron members in the exterior, showing the location of the transfer beams at Floors 4, 6, 9, and roof. It is more important, however, to understand that there were no spandrel beams in Floors 5, 7, 8, and 10. (Jensen & Halstead, Ltd., Chicago)

Second, he did not initially refer to the masonry as a covering, but always stated that he had embedded the iron column within the masonry pier in order to reduce the size of the piers and, thereby, maximize the amount of daylight entering the interior;

Jenney, Demolition of the Home Insurance Building, 1931. (Tallmadge, The Origin of the Skyscraper)

Third, unlike a skeleton frame, Jenney had filled his iron columns with concrete, which is completely unnecessary in a skeletal-framed building (with the exception of contemporary composite structures);

-Fourth, the lintel pans were not one continuous piece of iron that spanned from column to column (therefore, they were not a “beam”) but comprised of two pieces, not mechanically connected, that spanned only from a column shelf to the intermediate mullion, thereby offering no rigidity to the structural bay whatsoever; 

– Fifth, the lintel pans were also not bolted to the columns, so rigidity of the mullion/lintel assembly was gained through the masonry in the spandrel wall;

-Sixth, the exterior brick facing of the piers, whose thickness increased to 12 inches at the corner and entrance piers, was not supported on the iron column at any point, thus it was continuously bearing for eight stories from the granite piers. (remember that Jenney had notched the pans so that the facebrick could run continuous without any connection to the spandrels in an attempt to minimize cracking in the facebrick should the spandrel rotate caused by differential settlement).  In fact, Jenney had gone so far as to specify a very conservative technique of bricklaying for the piers’ face brick to achieve a stronger-than-usual assembly to keep the cross section of the masonry piers to a minimum.  Selected hard brick was used with a strong cement, not lime, mortar and was laid up in very tight, solidly packed joints.  This would have been entirely unnecessary if Jenney was supporting the face brick on the iron frame at each floor. The importance of this point is that the concept of the iron frame is to completely support its masonry enclosure, which it definitely did not do in this building;

-Seventh, as the columns typically extended laterally unbraced by iron beams for two stories (the spacing of the transfer beams that supported the mullions), and in the middle of the building for three stories, the columns more typically relied solely on the rigidity of the spandrel masonry interacting with the masonry pier to stabilize the connection against lateral loads and to brace the columns at each floor against buckling;

-Eighth, and finally, the iron frame with its loosely bolted and clamped connections could not have resisted any wind loads.  

What I have tried to show is that Jenney’s detailing was consistent with what he had originally claimed was his objective: he had embedded the iron column within the masonry pier that then allowed him to reduce the size of the masonry piers’ cross-sections.  Jenney’s structure in the Home Insurance Building did not generate much contemporary attention or acclaim in the U.S., or for that matter, even in Chicago, during its construction nor immediately following its completion. Was there any reason for such construction to have done so?  Most likely it was viewed by Chicago’s architects and builders as an eccentric curiosity because I am not aware of any Chicago architect that employed Jenney’s details in any building in Chicago.  The Home Insurance Building was simply just one of a handful of skyscrapers that were under construction in Chicago during 1884. 

Solon Spenser Beman, Pullman Palace Car Building, Chicago, SW corner of Michigan and Adams, 1883. (J.W. Taylor: Chicago Historical Society)

Even during its construction during the latter half of 1884, Jenney himself modestly spoke of S.S. Beman’s Pullman Building as the highpoint of Chicago’s architecture.  In fact, as the Home’s iron columns began to be erected in August 1884, Inland Architect stated that the commission for the Union League Club, and not the Home Insurance Building was “the greatest compliment Mr. Jenney has yet received professionally.”   Union League Clubs had initially sprung up in the North during the Civil War and had naturally subsided once the war had been won, but by 1880 it was evident to these men who had defended their country earlier, that the country was once again inching ever closer to civil war, but this time the enemy was Socialism.  So Union League Clubs were reestablished nationwide in 1880 purposefully “to encourage and promote by moral, social, and political influence, unconditional loyalty to the Federal Government, and to defend and protect the integrity and perpetuity of this Nation.”

William Le Baron Jenney, Union League Club, Chicago, SW corner of Jackson and Custom House Place, 1884. (Chicagology.com)

If Jenney’s use of iron in the Home Insurance Building had been considered to have been of a revolutionary nature, surely it would have been quoted in any of the obituaries for Daniel Badger who died in November 1884 and was referred to as “the first person in this country to use iron on a large scale for building purposes.”  Not surprisingly, following Jenney’s description of its structural system at the 1885 A.I.A. convention in October, the Home Insurance Building and the potential of its “unique” structural system were not discussed for the next two and a half years in local or American trade magazines or conference proceedings.  In fact, nobody in 1885 had the time to worry about such esoteric points as the construction market in Chicago was still completing the erection of all those buildings that were started in 1884.  

And even once this issue had eventually ignited in the construction press, there were still those in Chicago who, not for a moment, gave the legend any creditability.  Peter B. Wight, who  outlived almost all of those in the Chicago School, was the fireproofing contractor not only for the Home Insurance Building, but also many of the other buildings that would be posited for these honors, later claimed to have introduced Jenney to Normand Patton, Chicago’s leading designer of iron structures, in order to help with the design of the iron elements planned for the Home Insurance Building: “Jenney could talk building better than any man I knew, but he knew very little how to design and construct them and depended on others.” In fact, in 1950 a former Jenney employee, Elmer C. Jensen, who had entered Jenney’s office in March 1885 as an office boy and became a partner in the firm in April 1905, had admitted that he was always puzzled over the fact that “Major Jenney never made any claim that he had originated the skyscraper principle.”

“Frame-construction,” Burnham and Root, Reliance Building, 1890, 1894. (Online)

Therefore, if one adopts the definition of a skyscraper that is a tall building constructed solely with a metal skeleton frame, one needs to ascertain what was the first such tall building erected, for it was not the Home Insurance Building.   So when did the Home Insurance Building and its structure become such a contentious issue?  There will be an event that will spark the argument, but this won’t occur until 1888.  I think the time is overdue for this urban legend to be laid to rest.  Therefore, if you hear of anyone still citing the Home Insurance’s reputation, feel free to bring this post to their attention.  I will be more than happy to debate anyone at any time about this issue.  In fact, I’ve already laid out my opening arguments above.


Larson, Gerald, “Toward a Better Understanding of the Evolution of the Iron Skeleton Frame in Chicago,” Journal of the Society of Architectural Historians, March 1987, pp. 39-48.

Tallmadge, Theodore E. The Origin of the Skyscraper-The Report of the Field Committee. Chicago, 1934.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Jenney, Home Insurance Building. Surviving fragment of the iron structure in the Museum of Science and Industry. Note the stub spandrel beam (at the left of the column) that the Field Committee chose to include in the fragment left for history. As this beam was located in only three of the eight floors that were “skeleton-framed,” the committee attempted to mislead future historians about the true nature of Jenney’s structure, (Author’s collection)

It appears that as the building had increased in height from the initial seven floors of February 19, 1884, to the final ten stories of April 28, Jenney became concerned about the size of the masonry piers in relation to the need for daylighting (just as Baumann had likewise identified) and most probably began to experiment during the latter part of this period with embedding iron sections within the masonry piers that would support the floor beams in order to keep the piers’ cross section to a minimum.  This concept of embedding iron sections within a masonry structure to augment its capacity was consistent with an article that Jenney had published in the preceding year, in which he revealed his understanding of iron framing just before he had received the Home commission:  Educated architects in Europe… have been working with and writing on the combination of stone, brick and iron, in the street elevations of buildings.”  In other words, he did not mention the concept of an iron frame supporting its exterior masonry curtain wall but spoke instead of the structural combination of brick and iron.  This combination clearly reflected his French training and familiarity with French theorist Viollet-le-Duc’s ideas about the use of iron and masonry.  

Jenney, Home Insurance Building. Eighth floor plan. (Tallmadge, The Origin of the Skyscraper)

The building’s interior structure was the by-then standard iron frame protected with Wight’s terra cotta casings.  Also standard were the two masonry bearing party walls on its north and east that ran the entire height of the building and provided much of the building’s lateral stability.  

Jenney, Home Insurance Building. View of SE corner. Note the continuous masonry bearing wall along the east lotline. This shows the late addition of two stories. (Rand McNally view #5)

In fact, even the first two stories of the street fronts also were loadbearing rock-faced granite piers, battered in thickness from 4′-0″ at the base to 2′-10″ at the third floor.  Constrained by the building code’s requirement for masonry exteriors, the only detail in which Jenney had departed from standard Chicago construction of the early 1880s was his insertion of a rectangular, concrete-filled cast iron section within the exterior masonry piers in only the upper eight stories of the two street fronts.  In a sense, Jenney had inverted the structure of the Opera House Block, except that Cobb & Frost had also included spandrel beams (see below) and used the exterior iron columns in the first two floors to support all, and not just a portion, of the weight of the floors above. 

Jenney, Home Insurance Building.  Reconstruction of the structural detailing of the exterior piers.  (Drawing by Deborah Cohen Heller and Maxwell Merriman)

The iron sections were story-high, hollow cast-iron sections that supported the floor beams.  These sections were set on the top of the granite piers at the third floor and were bolted one on top of another, helping to support the upper seven floors and roof.  These sections were cast with shelf brackets to support two 12-inch deep wrought iron floor beams.  These beams were loosely bolted to the column by a single bolt that passed through the beam webs and connected them to a spacing bracket that was also cast with the column.  As tolerance was needed for erection, the holes were larger than the bolt, leaving the connection with a considerable amount of play.  Therefore, Jenney had incorporated a clamp that was a one-inch diameter wrought iron rod that was bent at one end and placed into a notch cut into the top flange of both beams.  The rod on the other end was threaded, allowing it to be connected to the column by a nut placed inside the column, thereby pulling the beams tight to the column face, after which the iron column was filled with concrete.  The concrete-filled iron column was then surrounded with masonry that at times exceeded twelve inches in thickness, creating a solid cross section in the building’s exterior piers.  In the first article he published on the building in the December 1885 issue of Inland Architect, rather than describing this technique as wrapping or enclosing the iron column with a masonry skin, Jenney stated that he embedded the iron column within the masonry pier: “a square iron column was built into each of the piers in the street fronts.”

Jenney, Demolition of the Home Insurance Building, 1931. (Tallmadge, The Origin of the Skyscraper)

So far, so good, but now Jenney’s structure becomes more “complicated” (I choose my words carefully).  Jenney was very concerned about the potential of differential settlement in his first tall building.  (This was evident in the title of a paper he delivered at the October 1885 A.I.A. convention, “The Construction of a Heavy Fireproof Building on a Compressible Soil.”)  He was not at all reassured by contemporary reports of the foundation problems in all three of Chicago’s new large public buildings, the Post Office, the City Hall (not yet completed!), and the Board of Trade’s tower (still under construction) that surely would have made him overly-cautious in how he would detail the structure to minimize any problems.  With these reports fresh in his mind, the last thing that Jenney would have wanted to detail in the Home Insurance Building would have been a rigid framed structure.

Drawings of Cracks in the Board of Trade due to the differential settlement of the Tower. Chicago Tribune, January 21, 1894. (Chicagology.com)

If Jenney had conceived this structure as a skeleton frame, he would have simply placed an iron spandrel beam connected at both ends to the columns that would have supported the window wall above. This Jenney did not do.  One can imagine any number of reasons for his decision: my best guess is that a long iron beam at every floor in this location was too expensive, because this was exactly what Jenney did not detail.  Instead of spanning this distance with a single iron beam upon which he could then place the masonry spandrel panel and paired windows, he still placed the conventional vertical structural iron mullion between the windows and then used a shallow iron pan to span between the pier and the mullion, i.e., he broke the single span between the piers into two spans, that met at, and were supported by, the intermediate iron mullion.  This traditional structure of the paired window and mullion, as we have discussed before, had the inherent problem of differential settlement between the heavily-loaded piers and the lighter mullions because it was still conventional practice, even though Baumann had argued against it, to put the same size footing under both elements. This resulted in the heavier-loaded piers settling at a greater rate than the smaller mullions, transferring more and more load to the mullions, and often resulted in cracking around them. Chicago’s poor soil only seemed to exacerbate this problem, as we saw in Richardson’s American Express Building (see Vol. One).

Left: Foundation problem with intermediate piers. Right: Foundation solution for alternating piers and mullions: to transfer the load in the intermediate mullion to the main piers. (Baumann, Foundations)

Therefore, instead of using iron beams to span between the piers, Jenney detailed cast-iron lintels in the form of four-inch deep hollow pans, also filled with concrete like the columns, that spanned the distance between a column shelf bracket and the intermediate cast-iron mullion.  The cast-iron lintel pans were as wide as the masonry spandrel walls that were constructed on top of them.  As if the street fronts were still considered to be bearing walls, the spandrels, for no other conceivable reason, increased in thickness along with the piers, as required by the building code, from 20 inches in the top three floors to 24 inches in floors 5-7, to 28 inches in floors 3 and 4.

The lintel pans were not bolted to each other, to the mullion, or to the column brackets, but simply rested on these surfaces, relying solely on the supported masonry knee wall that was bonded into the masonry pier, to hold the armature laterally in place.  The lack of bolts may have been a technique on Jenney’s part to impart some rotational flexibility at the column/spandrel connection to accommodate differential settlement of the piers.  This flexible joint was augmented by notching the front of the iron lintel four inches back from the face of the pier, which allowed the pier’s exterior face brick to continue past the lintel so that the pier’s face brick would not be supported at any point along the lintel.  This detail minimized the potential of the face brick to crack if an iron spandrel rotated due to the settlement of an adjacent pier, but it also meant that the pier’s eight-stories of brick facing was continuously self-supporting from the granite piers at the third floor and was not supported at each floor on the iron column. 

Jenney, Home Insurance Building. Section and elevation of structural iron members in the exterior, showing the location of the transfer beams at Floors 4, 6, 9, and roof. It is more important, however, to understand that there were no spandrel beams in Floors 5, 7, 8, and 10. (Jensen & Halstead, Ltd., Chicago)

The next decision was, how to bring the loads in the intermediate iron mullions to the foundation?  The easiest way to avoid the anticipated differential settlement between the piers and the intermediate mullions was to transfer the mullion loads over to the main piers, thereby the mullions would never reach the ground.  However, if this was done not with a single transfer beam at the lowest floor, but with a series of transfer beams as Jenney had detailed, the loads in the mullions would be relatively uniform, and therefore the mullions’ cross-section would not have to increase as the piers did, keeping the windows as large in the lower floors as they were in the upper floors.  Jenney, therefore, placed iron transfer beams to carry the mullions’ loads to the piers immediately above the cast iron lintel pans at the fourth floor (four 7-inch I-beams), sixth floor (three 15-inch I-beams), ninth floor (two 12-inch I-beams), and roof (two 15-inch I-beams).  These transfer beams also nominally laterally tied the iron columns in the piers together (especially at the roof), thereby creating what one might optimistically call a “skeleton frame.”  However, if it was Jenney’s intention to actually create a rigid iron skeleton frame in the street fronts, these beams should have been introduced at every floor to not only carry the spandrels’ masonry, but also to laterally brace the iron columns at each floor to minimize their buckling length since the iron lintel pans were not bolted to the columns and, therefore, any bracing provided by them was negligible at best.  As constructed, the iron columns in floors 6-8 stood laterally unbraced for three stories.  Consequently, without the masonry and the concrete filling, the iron armature in the exterior would not only have been structurally unstable, but also have been very difficult, if not impossible, to erect it two or three floors ahead of the stiffening masonry of the piers and spandrels as some reports had claimed (the concrete filling of the multiple-storied hollow section would also have been impossible). 

Jenney, Home Insurance Building. The exterior iron structure overlayed the building’s elevations, showing the lack of spandrel beams in Floors 5, 7, 8, and 10. (David Burwinkel)


Larson, Gerald, “Toward a Better Understanding of the Evolution of the Iron Skeleton Frame in Chicago,” Journal of the Society of Architectural Historians, March 1987, pp. 39-48.

Tallmadge, Theodore E. The Origin of the Skyscraper-The Report of the Field Committee. Chicago, 1934.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Henri-Jules Borie, Aérodômes, Paris, 1867 redesign of his original 1865 proposal. (Design Quarterly, 85, 1972)

In Volume One I gave you my definition of the “skyscraper principle:” a building design using the elevator to include more floors than the pre-elevator limit of five-six stories, in order to increase the building’s rental return to help pay for the high cost of the land upon which it was planned to be built.   I also have identified Henri-Jules Borie’s Aérodômes of 1865 for Paris as the earliest proposal, that I have found, to build tall buildings exploiting the advantages of the elevator, as well as Henry Hyde’s Equitable Building in New York in 1867 as the first manifestation of the idea. Many historians have pooh-poohed these early skyscrapers as unworthy of the term because they are not “tall enough” to merit the appellation.  Once again, we have here the tendency to evaluate the past on present terms.  Of course, if one has grown up with 10+ storied buildings, one is used to this urban datum that must be truly broken for a tall building to qualify as a skyscraper.  But as the photo below shows, if one has grown up in a pre-elevator city in which the urban datum is five stories, then, indeed, a ten-story building looked very high and deserved to be called by a new term!

John J. Flanders, Mallers Building, Chicago, 1884. Compare the height of pre-elevator Chicago at the far right with the new skyscrapers. (Van Zanten, Sullivan’s City)

Chicago’s heady atmosphere of 1884, generated in part by the unsurpassed height of the Board of Trade’s tower, was such that the local media began to adopt the term “skyscraper” for the tall buildings then under construction.  I am not interested in the history of the term that over time had been applied to such diverse objects as tall horses to the tall masts of sailing ships.  John Moser, an architect from Atlanta, had used the term “sky-scraper” in June 1883 in an article, “American Architectural Form of the Future,” that was published in American Architect.  In pursuing an appropriate form for the architecture of the United States, he believed that:

“a public building should always have something towering up above all in its neighborhood, to proclaim the fact afar that here is where McGregor sits, here is the head of the table.  It should be in our case slender, vigorous, bold, rakish and daring… This form of sky-scraper gives that peculiar refined, independent, self-contained, daring, bold, heaven-reaching, erratic, piratic, Quixotic, American thought… The capitol building should always have a dome.  I should raise thereon a gigantic “sky-scraper,” contrary to all precedent in practice, and I should trust to American constructive and engineering skill to build it strong enough for any gale.

John Moser, Sky-scrapers, “American Architectural Form of the Future,” Atlanta, 1883. (American Architect, June 30, 1883)

It is interesting to note that although Moser associated the term “sky-scraper” with very tall structures, he reserved its use for all buildings except commercial structures. 

In August 1884, the Real Estate and Building Journal reprinted an article from the Daily News that listed what it considered to be Chicago’s “skyscrapers,” many of which had been built in the prior year.  After reading it, one could easily make the case that W.W. Boyington could deserve to be known as “the father of the Chicago Skyscraper.” 

Boyington, Chicago Board of Trade. La Salle Street south from Adams Street. (IChi-00253, Chicago Historical Society)

In descending order of height, these were:

-Boyington’s tower of the Board of Trade, 303′ (Sperry’s Corona had increased this to 322′); 

-[Eidlitz’s Dearborn Street Station tower, 195’];

-[Beman’s Pullman Town Watertower, 195’];

-Boyington’s Water Works Tower, 175′; 

-Boyington’s recent addition of twin towers for the La Salle Street Station, 170′;

-[Boyington’s Office Building behind the Board of Trade, 10+ st.]

-Beman’s recently-announced 13-story office building for Marshall Field to reach 170′ (to be discussed later in this chapter); 

-Beman’s Pullman Building, 165′; 

-Boyington’s Royal Insurance Building, 164′; 

-Burnham & Root’s Insurance Exchange, 160′; 

-Jenney’s Home Insurance Building, 159’; 

-Burnham & Root’s Counselman, Calumet, and Montauk Buildings, 145.’ 

W.W. Boyington, La Salle Street Station with addition of the 170′ tall towers. (Douglas, Rail City)

So Chicago’s own professional press had lumped the Home Insurance Building (that at this date was only two stories out of the ground with the ironwork scheduled to be started in September) as only one, and one of the shorter ones at that, of a dozen of Chicago’s buildings into the catagory “skyscrapers.” Obviously, in 1884 the Home Insurance Building was not considered to be Chicago’s first skyscraper.

So if the Home Insurance Building was not considered to be Chicago’ first skyscraper at the time of its construction in the Chicago press, how did it eventually become associated with the reputation of being the first skyscraper?  This legend has a long historiography that I will dip into now and then when appropriate to do so, but I am not interested at this point to discuss this in depth.  Chicago’s advocates, acknowledging that New York had erected a number of buildings with 10 or more stories before 1884, in order to claim Chicago as the birthplace of the skyscraper, would eventually settle upon the idea that to be a skyscraper, a building must be skeleton-framed in iron. Therefore, they eventually settled upon the Home Insurance Building as being the first such building: a skyscraper erected solely with an iron frame.  Although this was not factual, as we will see in the next section, the legend of the Home Insurance Building was born and still does not die easily (I’ve been trying to set the historical record straight since 1985.) I will discuss over the next few chapters how this legend evolved after 1888, and why this date is important, but for now, let’s review the development of iron framing before Jenney had incorporated his version of the technique in the Home Insurance building in March 1884.

James Bogardus, McCullough Shot Tower, New York, 1855. (Silver, Lost New York)

I have reviewed in great detail how iron framing developed first in Great Britain, then in France, and eventually in the U.S.  In the U.S., the technique was perfected and patented by New Yorker James Bogardus.  The structure most noteworthy was his McCullough Shot Tower of 1855.  In this tower Bogardus had erected a self-supporting iron frame and then enclosed its interior by erecting brick panels at each level of the iron framing: the technique that will eventually be used to build skyscrapers.  The problem with Bogardus’ system was the exterior iron structure was not protected from fire.  I have reviewed how Peter Wight and others had solved the fire protection problem with interior iron framing with the use of terra cotta casings, so that all of Chicago’s tall office buildings erected in the early 1880s were constructed with an internal iron frame that was fireproofed.  The iron skeleton was then enclosed around its perimeter for protection with exterior masonry bearing walls.  As these buildings quickly grew taller, their exterior brick walls correspondingly grew thicker (and heavier) in order to support the increased weight of the floors above.  This conflicted head-on with the desire to make the windows as large as possible to maximize the daylighting of the interior.  The problem faced by Chicago’s builders of the taller office buildings of the 1880s was how to duplicate the excellent quality of daylighting that was achieved with the cast iron front of the 1850s, without sacrificing the fireproof characteristics of the red brick box of the 1870s.  

Post, Produce Exchange, Photo of Construction showing the iron skeleton framing in the lightcourt walls. (Landau and Condit, New York)

Therefore, the iron frame in 1883 was not an unknown technique waiting to be “invented” as many historians have claimed; by this date it was a well-developed system of construction. George Post was in the process of erecting just such construction in the New York Produce Exchange.  French Engineer Gustav Eiffel had already used this concept in the Statue of Liberty that had been standing in Paris for all to see since October 1881, the first illustration of which had been published in Sept. 1883.

Statue of Liberty under construction in Paris, 1883, Génie Civil, 1883. First Image of the structure of the Statue of Liberty reprinted in the American Press, American Architect, September 1883. (Loyrette, Eiffel)

By 1881 iron construction was being given more exposure in Chicago’s architectural press.  Across the street from the Montauk Block, then under construction, Haverly’s Theater was being erected.  Although the exterior consisted of solid brick walls, the supports of the galleries were all iron, leading Real Estate and Building Journal in July 1881 to state: “It is possible and feasible to construct the auditorium entirely of a light iron framework, which would make it practically fireproof, and every theater should be built this way.”  The same issue contained an article on the newly constructed Cape Henry Lighthouse on Chesapeake Bay: “It is 155′ from base to top.  The exterior, which is octagonal in shape, is constructed of cast iron.  Every story is solidly bolted together by heavy cast iron floor plates… 7,000 pounds of bolts were required.” This article may well have been the inspiration for the structure used by Beman in the Pullman water tower that had been made by Bouton and Pullman’s Union Foundry and Pullman Car-Wheel Works that was also responsible two years later in 1883 for producing the largest iron columns built during the 1880s, the massive phoenix columns for the tower of the Board of Trade. 

S. S. Beman, Pullman Water Tower, Town of Pullman, 1880. Section, Elevation. The 100′ tall iron columns that support the 500,000 gal. tank. (Online)

During the summer of 1883, the 16-sided Panorama Building at the corner of Wabash and Hubbard Court (Balbo) was under construction to house a 400′ long by 45′ high painting of the Battle of Gettysburg.  Designed by Bauer & Hill, the building’s 130′ diameter clearspan was framed entirely in wrought iron whose interior was enclosed by brick walls:

“The walls are fifty feet ten inches high, roof dome-shaped.  The constructive part of the building is entirely of wrought iron.  Iron pillars being anchored to the foundations of the piers run to the roof and continue in arched ribs to a center ring-piece, which supports a ventilating cupola.  The surrounding walls are to be entirely of brick, ornamented with galvanized belt courses and cornices.”

The success of the city’s first panorama prompted the erection of a second such building across the street from the first one in the spring of 1884, to poignantly house a painting of the 1871 Siege of Paris.  Chicago’s leaders were not about to let the actions of Paris’ Communards in 1871 fade from memory with this warning of how the event ended.  Although the building was designed by New York architect, John M. Carrere, its construction was supervised by Jenney, at the same that he had just started to consider the use of iron sections in the Home Insurance Building.  

Boyington, Chicago Board of Trade. Note the skeletal nature of the structure surrounding the Trading Floor. (Chicagology.com)

In fact, in 1883 we began to see the reemergence of iron framing in the exteriors of Chicago buildings.  The first such instance appears to have been Boyington’s Board of Trade Trading Floor (image), where, with the apparent assistance of Normand Patton, iron columns at the building’s perimeter were used to support the heavy iron trusses that spanned the 170’ wide space. These were fireproofed by being encased in masonry.  Next in line appears to have been Cobb & Frost’s use of exposed iron framing in the first two floors of the Opera House Block.  In summary, in March 1884, when Jenney was thinking about using iron sections in the exterior piers of the Home Insurance Building, iron framing for multistoried buildings was already an accomplished fact, not a new idea that he was the first to invent.

Cobb & Frost, Chicago Opera House Block, Chicago 1884. Detail of the exposed iron framing in the first two floors. (Condit, Chicago)


To prove this point, Frederick Baumann, who had established a reputation as Chicago’s leading theoretician on building construction with his development of the uniformly-stressed pad foundation in 1873, appears to have been one of the earliest Americans to apply the concept of Bogardus’ independent iron frame to the construction of tall buildings, since it had fallen out of favor following the Civil War, in an article, “Improved Construction of High Buildings,” published in the March 15, 1884, issue of Sanitary News.  

“The design is to erect on foundations a firm and rigid skeleton, or hull, of iron, and cover it at once with a proper roof… The practicability of erecting buildings on Chicago soil, twelve and more stories high, then becomes a fact. Light, the great desideratum in all city buildings, is secured, even on the lowest-the most valuable-floors, whereas, otherwise, the necessarily broad piers would be a hinderance.  The piers may not only be made narrow, but shallow-twenty-seven inches at the most, thus, again making a saving of light..  The iron uprights are to be provided with a series of projecting brackets for the purpose of anchoring and supporting the parts forming the exterior enclosure.  These supporting brackets will be so arranged as to permit an independent removal of any part of the exterior lining, which may have been damaged by fire or otherwise.  The iron-floor girders are securely fastened to the outer posts at both ends.  This imparts firmness to the structure”

Baumann later stated that he had already publicly presented his scheme at an earlier lecture, so first public discussion of his ideas would have necessarily preceded the article by, being conservative, at least two weeks to account for writing, editing and printing.  This, then pushes the date of Baumann’s first presentation of the concept conservatively back to at least March 1, 1884, if not even earlier.  At the same time, Jenney had received the commission to design the Home Insurance Building.  According to Jenney’s personal notes, the first mention and calculation of the iron sections that he planned to embed within the building’s exterior masonry piers was dated April 17, 1884, over a month after the publication of Baumann’s ideas. 

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


William Le Baron Jenney, Home Insurance Building, Chicago, 1884. (J.W. Taylor, IChi-00989; Chicago Historical Society)

The third of the large buildings granted a building permit during the first week March 1884 was the Home Insurance Building. The project was initiated by developer Edward C. Waller, who had been a close friend of Daniel Burnham’s ever since the two of them had traveled to Nevada in search of silver in 1869.  While Burnham had chosen the path of architecture as an adult, Waller had gravitated to real estate development and had gained a reputation as a major player in downtown properties.  Waller had assembled the lots on the northeast corner of Adams and La Salle, opposite the “temporary” city hall or “Rookery” during 1883 for the British-owned insurance company to erect a new office building. The company apparently had initiated a design competition in February 1884 for a building adjacent to the Calumet Building and diagonally opposite from the Insurance Exchange. 

Map of Loop, 1884. (Author’s collection)

Managing the competition was the company’s Chicago agent, Arthur C. Ducat.  Ducat was an Irish immigrant who at the age of 21 had settled in Chicago during 1851, finding employment in engineering and as insurance agent, developing a keen interest in finding better methods of fire protection for buildings.  He had fought in the Civil War, raising to the rank of Lt. Colonel before his service had ended in late Oct. 1862. He had then gone on to serve as the Inspector General in the West, when he more than likely made the acquaintance of Maj. William Le Baron Jenney. After the end of the War, Ducat returned to Chicago becoming the agent for the Home Insurance Company, and also a Maj. General in charge of the Illinois National Guard.

By the time of this competition, Jenney had fallen into the role of the elder statesman among Chicago’s architects.  His practice had fallen from its heyday during the post-fire reconstruction, to the point where he had not designed a major building (the miniscule five-story First Leiter Building notwithstanding) in the intervening ten-year period since the Portland Block and the Lakeside Building of 1873, that, coincidentally, was located diagonally to the east across Adams Street from the site.  Instead, Jenney had become a man of letters: teaching architecture briefly at the University of Michigan in 1876 during the depth of the Depression, handling correspondence for the A.I.A., and lecturing on architectural history at the Art Institute. While these pursuits were respectable, they were hardly in the same league with the contemporary trail-blazing activities of the big building designers Boyington, Beman, and Burnham & Root.  The true measure of the professional stature of Jenney’s office in the early 1880s was best exemplified in Peter C. Brooks’ decision, who owned Jenney’s Portland Block, to hire Burnham & Root, and not Jenney, to design the Montauk Block, Chicago’s first skyscraper.

William Le Baron Jenney, Portland Block, Chicago, 1872. (Turak, Jenney)

Had Jenney not been a good friend of Ducat, it is reasonable to assume that Jenney’s career would have faded into obscurity.  Instead, Jenney recalled later in life that Ducat had given him the chance to design his first tall office building: “In 1883 [sic-it was in 1884], when the Home Insurance Company proposed to erect a building in Chicago, Ducat (who was the leading agent in the West) kindly recommended me to be their architect.”  The first report of the competition was in late February 1884, that correlates with the first mention of the Home Insurance Building in Jenney’s personal notes, dated February 19.  The building at this date was to be only six stories plus a basement:

“The basement story to be one step up from the sidewalk, similar to the Boreel Building… This would make the building 84′-5″ high [six stories plus basement], if another, [it] would be 96′, which is high enough and I would object to it being any higher… The basement to be of some suitable stone to be decided upon.  The rest of the building to be of brick with terra cotta or molded brick trimmings.

When the building committee from New York arrived in Chicago during the first week in March to review the competition drawings for the new building, that were reported to have been submissions by three different architects, it apparently had already increased the height of the building because the permit obtained on March 1, was for an eight-story plus basement structure.  Suspiciously, it was reported that even though a winner had not yet been chosen (Jenney would be officially chosen two weeks later), the permit was taken out upon the plans of Jenney, and that he, upon the orders of the company (and undoubtedly at the encouragement of Jenney’s friend, Ducat), had already begun to let the contracts for the cut stone and other materials.

Jenney, Home Insurance Building. Eighth floor plan. (Tallmadge, Skyscraper)

The following month, Inland Architect reported that Jenney’s design had indeed been chosen the winner from plans submitted by a half dozen of Chicago’s best architects.  The design continued to be refined during the spring of 1884; the final height was set on April 28, 1884, at 150′ with nine stories plus basement.  In plan, Jenney first placed single-loaded corridors along both street fronts. The remaining two lotlines were protected by code-required masonry bearing walls.  The lot was sufficiently wide for Jenney to “slip-in” two offices in back of the Adams slab turning it into a double-loaded corridor.  This required the elevator core to be pushed deep enough into the lot to make a lightwell that also allowed one office to be located on the opposite side of the lightwell.

William Le Baron Jenney, First Leiter Building, Chicago, 1879. The two upper floors were added in 1888. (Zukowsky, Metropolis)

As was the case in the design of the Portland Block and the First Leiter Building, Jenney’s primary concern in the design of the building’s elevations was to maximize daylighting of the interior.  He chose the pier-and-spandrel language of the Leiter Building for seven of the ten floors, retaining the use of the arch to emphasize the termination of the base layer in the second floor and the termination of the building in the tenth floor.  As he had done in the Portland Block and the First Leiter Building, he also layered the elevation with his characteristic contrasting light stone banding at every floor level.  The horizontal accent of the building allowed the design to gracefully accept the anticipated addition of extra floors at a later date.

Burnham & Root, Insurance Exchange, Chicago, 1884. Southwest corner of La Salle and Adams. (Hoffmann, Root)

The obvious lack of clarity in his design of its elevations is straightforwardly explained as this was his first attempt at designing the elevation of a tall building.  He began where most Chicago architects had started (Cobb & Frost being the exception) with a stone base.  Quite correctly, he improved upon Root’s adjacent Insurance Exchange by making the stone base two stories tall that gracefully accepted the triumphal-arched entry.  He also took Root’s balcony located over the entrance at the fourth floor but did it one better: he made a second balcony overlooking the triumphal arch, and just for good measure, inserted a third, albeit subordinate balcony in between these, creating a threesome of balconies.  

Where Jenney got into trouble was in the eight-storied brick body in which instead of treating each floor alike as he had done with the First Leiter, Jenney followed the current fashion of grouping floors together into larger layers with colossal pilasters.  Jenney followed Root’s Insurance Exchange and Boyington’s Royal Insurance Building by placing pilasters at the corners and at the location of the entrance on both street fronts.  He used the pilasters to create a sequence of base:2:3:2:1 that was very similar to Post’s Mills Building in New York.

Jenney’s detailing of double windows also echoed the Mills Building as well as the Royal Insurance Building.  The top floor again revealed the influence of the Royal Insurance’s Quincy facade in the semicircular arched windows that Jenney had originally rendered to have been sculpted panels as Boyington had detailed.

Jenney’s larger horizontally-grouped layers were reinforced with continuous stone cornices.  This, in and of itself would have been fine, except for those incessant horizontal bands of light stone at each floor.  The resulting composition of the multi-storied layers was simply unresolved, for the continuous vertical piers not only clashed with, but were visually overshadowed by the highly-contrasting stone horizontal bands.  The most awkward of all the detailing in the building, however, occurred in the pilasters in the middle, three-story layer, where Jenney naively allowed the subordinate stone banding to harshly continue through the would-be dominant brick pilasters at floors 6 and 7, creating a pair of unbroken horizontal lines around the building that resulted in a cacophony of architectural forces.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Cobb and Frost, Chicago Opera House Block, Chicago, SW corner of Clark and Washington, 1884. (Art Institute of Chicago)

Fellow Union League Club members Charles Henrotin (stockbroker) and William Kerfoot (real estate) simply followed the Palmers’ lead by hiring their architect for the Opera House Block from the “bluebloods” within the Club’s membership list.  While Cobb & Frost had been given superb reviews for their design of the Union Club and the Palmers’ mansion, both of these commissions were of a “residential” scale.  This project to design the city’s largest auditorium and surround it with a ten-story office building, however, was completely “out of their league.”  Besides the snobbishness of hiring a fellow club member, Henrotin and Kerfoot may have been also convinced that the young architects could “do it” when reminded that Fuller had been Peabody & Stearns’ managing partner who had designed the nine-story United Bank Building in New York.  Clark & Fuller were awarded the construction contract for the ten-story Opera Block.  

Peabody & Sterns (George Fuller), United Bank Building, New York, 1880. (Online)

Given the dimensions of the site (107’ along Washington and 187’ along Clark), Cobb & Frost placed the 2300 seat auditorium in the interior of the site, running north to south with the stagehouse on the south side of the lot. They then lined the two street fronts with stores on the first two floors that were then topped with an eight-storied office slab on the two street fronts.

Cobb and Frost, Chicago Opera House Block. Left: View of Theater House within the confines of the office slabs. The stage house with its gable roof is visible at the back of the site. (Rand-McNally, View #19); Right: Rear walls’ elevations. It appears that the rhythm of the windows in the Clark St. slab is the same as that in the street elevations. (Art Institute of Chicago)

While the Clark St. slab had only sufficient dimension for a single-loaded corridor, the Washington St. slab appeared to be double-loaded (the 78’ long dimension of the auditorium combined with a 60’ width office plan would had left about 50’ for the stage). Access to the auditorium’s lobby was provided by the theater’s famous illuminated canopy on Washington Street.

Cobb and Frost, Chicago Opera House, Detail of exposed iron framing in the first two floors. (Siry, Auditorium)

The enigma of this building continues to be whether or not its exterior walls were constructed with an iron skeleton frame (historians Joseph Siry and Edward Wolner say it was, Thomas Leslie says it was not).  At first glance, this was most decisively the largest building yet erected in Chicago that had a pier-and-spandrel elevation.  With exception of the soon-to-be-gratuitous arcade in the eighth floor, the elevations were a rational expression of a column-and-beam system.  We can compare the Insurance Exchange to the Opera House to see the visual/architectonic difference between a wall-with-windows vs. a pier-and-spandrel elevational concept (the wall has less glass and a greater horizontal accent due to the continuity of the wall across the surface).  The comparison also reveals that the spandrel depth in the Opera House was minimized, resulting in larger window openings that those in the Insurance Exchange. 

It was the lower two floors of the Opera House Block that aroused the interest of the local building community and still leads the historian today to the question of iron framing in the upper floors.  To accommodate the stores on the ground floor by creating windows as large as possible, Cobb & Frost used iron columns and beams in the exterior of the two street fronts to support the upper eight floors of loadbearing masonry.

Fuller had already used this detail in the United Bank Building and more than likely recommended its reuse. The reason for its use was logical:  the smaller iron column allowed the windows to be larger, thereby providing as much daylight as possible. This was a great benefit because the back of the stores in these two floors was a solid masonry wall needed to provide a fireproof separation between these and the theater. The smaller iron cross-sections also took up less floor space, thereby creating more floor area to be charged in the rental agreement. 

Cobb & Frost, Opera House Block. Plans of Main Floor and Balcony of the House. Note the solid masonry wall at the back of the balcony that would have continued around to the left to also separate the theater from the Clark St. stores. (Siry, Auditorium)

Curiously, after all the agitation over the past decade over the use of exposed iron structures, the iron columns and beams in these two floors appear to have been completely exposed, with no apparent means of fireproofing visible. (While the actual iron columns might have been fireproofed and then had an iron plate detailed over this to make it look like the actual structure was exposed, the column’s spindly dimensions lead me to say this was not the case.)  

The design of the elevations shows the influence of both Fuller’s United Bank Building and Root’s Insurance Exchange.  We can start with Fuller’s design of the United Bank Building in New York, that had also informed Root’s design of the Insurance Exchange, that then had influenced Cobb & Frost’s final design.  In the Bank Building, Fuller had used a composition of wider corner and central pavilion piers (that he also had carried into the building’s attic) to modulate what otherwise would been a very monotonous front elevation of repetitive structural bays.  Root had used this same motif, including its extension into the attic of the Insurance Exchange.  

While Cobb & Frost likewise had used this theme (detailing corner pavilions with wider piers) on the longer “front” of the Opera House building along Clark Street, they also felt compelled to reinforce the façade’s center by employing Root’s center bay design of the Burlington Building, i.e., the center bay comprised of paired windows (topped by elliptical arches) at each side with a narrower, but still paired window in the center. They also reprised Root’s device of displacing the floor levels above the balcony by one story, except here they interposed a blind arcade immediately above the tenth floor windows, that displaced the cornice and created a central attic that broke the roofline, marking the center and entrance of the building.

Left: Opera House Block. (Condit, Chicago); Right: The Insurance Exchange. (Hoffmann, Root). While Root has used the balcony to dislodge the belt course one story, Cobb & Frost have inserted a segment of a blind arcade in the cornice over the Clark Street entrance to dislodge the cornice to emphasize the center of the elevation.

This elevation has been typically overlooked in favor of the Washington Street elevation simply because most of the surviving photographs of the exterior are taken at such an angle that the Clark elevation is hard to discern.  Therefore, focusing on the shorter, less “important” Washington elevation historians find a slightly different rhythm with regards to the location of the wider piers.  In this elevation the wide and narrow piers alternate across the entire façade, which they do not do in the Clark Street façade.  Because the architects were forced to locate the theater’s entrance offset from the center by one bay to the right (the program demanded this?), one does not at first realize that the design of the Washington Street elevation still consists of a central and corner pavilions, as does the Clark Street façade, but indeed it does! Look carefully at the windows: the corner pavilions have two lines of single windows while the interior bays comprise of paired windows. (In the final design, they carried this same detail around the corner to the Clark St. elevation, although it is not as distinct because they continued the use of single windows in this elevation, as opposed to the paired windows in the Washington elevation.) Curiously, they still alternated the width of the piers across this entire facade. Was it coincidence that the wider piers lined up with the iron columns in the storefront or did this, indeed, express the fact that the wider piers contained a continuous iron column from the ground floors? (Unfortunately, this line of reasoning falls apart on the Clark St. facade where the piers, after the corner pavilions, reamained constant.)

Cobb and Frost, Chicago Opera House Block. (Condit, Chicago)

Meanwhile, the Opera House’s horizontal composition or layering of the elevations was quite similar to the overall arrangement of the Insurance Exchange.  The only difference between the layering of the two buildings was Cobb & Frost’s removal of Root’s awkward belt course in the fifth floor, that lowered the four-story arcade one floor. The extra floor was then moved to the top of the building where it was grouped into a two-story layer.  

They reprised Fuller’s square turrets from the bank at the top of each corner, while the actual detailing of the arcade, bore a striking resemblance to the design by their former employers, Peabody and Stearn’s R. H. White warehouse.  

Above: United Bank Building. (Online); Below: Opera House Block. (Art Institute of Chicago)
Peabody and Stearns, R.H. White Warehouse Store, Boston, 1882.
(American Architect, September 15, 1883)

And now to address the structure in the exterior walls in the upper eight floors.  Looking at these elevations, one can easily imagine that the iron columns and beams in the first two floors were simply extended into the rest of the elevation, especially given the overall rectilinear grid of the façades, so for the sake of argument, let’s start by assuming this was the case.  The building was famous for the speed with which Fuller had completed its ten floors: from its start in mid-August to the start of December-it took only four months!  One could credit this record speed to the use of only skeleton framing throughout the building.  An article in Inland Architect in November 1884 only muddied the waters more: “some of the heaviest columns ever placed… with the corner column supporting all ten stories.” But the article never specified if those upper stories were of iron or of masonry.  I come down on the side of the argument that says no iron was used above the second floor in the exterior for these reasons:

1. Never in the contemporary professional press was it ever mentioned that the entire exterior wall was supported by an iron frame. (I use the same argument against the same claim made for the later Home Insurance Building-coming up next.)  It simply is still too early for such a paradigm-change in construction to occur.  If indeed its exterior was skeleton framed, then it would have been the first such building in Chicago, and history would have celebrated it as such, and not the later Home Insurance Building!!  However, Fuller, being the steadfast advocate for steel construction, was reported to have used all steel beams (I think this was actually limited to only the floor joists) in the interior framing.

2. I credit Fuller’s construction genius with the speed of construction.  Looking at the exterior, one can see that he has attempted to use repetition of the same element as many times as possible, to “keep it simple, stupid.” The fewer the number of differently sized windows, bricks, lintels, etc., the less thought the workmen have to put into their actions that resulted in more efficiency, hence, the increased speed of construction. Fuller will continue to innovate in construction techniques to reduce the time that it took to erect a building.  Probably the best example will be with the Tacoma Building, in which he had three teams of masons erecting the brick curtain wall starting at the same time on three different floors, rather than starting on the ground floor and laying one story at a time.

3. Fuller would use this same detail, putting nine floors (one more than the Opera House) of loadbearing masonry on a two-story high iron frame in the alley elevations of Burnham & Root’s Rookery two years later. If he had used an iron frame in the Insurance Exchange, I see no reason that he would not have also done the same in the Rookery. 

Burnham & Root, The Rookery, Chicago, 1885. Corner pier at the intersection of Quincy and the alley. Here Root and Fuller have taken iron skeleton construction to the next level: putting the glass facade in front of, rather than in between the iron columns and beams. Le Corbusier is usually given credit for this technique in his “free facade” concept of 1923. (Author’s collection)

Nonetheless, the Opera House Block’s two stories of iron framing marked the post-fire return of the use of iron skeleton framing in the exterior of Chicago’s multistory buildings. (This, of course, assumes that Boyington had used the iron columns and beams in the Board of Trade’s Trading Floor-only one story-only to support the trusses that spanned the Hall, while the office floors above were constructed with exterior loadbearing masonry.)  Fuller, with Cobb & Frost, had conceived detail this before William Le Baron Jenney had decided to put iron columns in the masonry piers of the Home Insurance Building (next to be reviewed).

Meanwhile, the Chicago Opera Block’s theater had opened in August 1885 to less than rave reviews.  Cobb & Frost had designed its house specifically for the “spectacular extravaganzas” staged by impresario David Henderson, designed to awe the middle-class audiences with glitz and over-the-top special effects.  Apparently, Cobb & Frost could not resist competing with Henderson’s “lack of good taste.”  One critic excoriated the interior’s gaudy decoration: “every advantage has been taken of the color scale, so as to obtain the greatest amount of glitter and glare.  There is a want of repose – some cool spot to rest the eye upon.  An endeavor has been made to gild refined gold and paint the lily, and the feeling aroused is more one of astonishment than admiration.”

While the negative response to their aesthetics could have been waived off as being subjective, Cobb & Frost’s lack of experience in the actual physical design of an auditorium was suffered by many who were crammed into the 2300 seats, as related by two critics: “By the way the people on the sides of the balcony stand up and crane their necks to look at the stage it is evident that the construction of the many seats in that quarter will have to be revised” for it “impresses one as less open and airy than most of the other city theaters, more compact, something of agreeable appearance having been sacrificed to the purpose of getting as many people as possible as close to the stage.”  The theater’s owners had to admit their initial error in hiring a firm without any prior experience in the design of a theater and hired Adler & Sullivan to completely remodel the auditorium’s interior once the theater’s premiere season ended in June 1886.  (see next chapter)


Siry, Joseph M. The Chicago Auditorium Building. Chicago: University of Chicago Press, 2002.

Wolner, Edward W. Henry Ives Cobb’s Chicago. Chicago: University of Chicago Press, 2011.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Cobb & Frost, Chicago Opera House Block, Chicago, SW corner of Clark and Washington, 1884. (Online)

In the Statue of Liberty, Eiffel had reworked James Bogardus’ technique of using an iron frame to support its masonry curtain wall in order to support Bartholdi’s copper curtain wall. The point here is that sheathing an iron frame in a non-loadbearing envelope (be it masonry or metal or glass-the cast iron front) had been in use since 1855 (earlier if we count the cast iron front).  What Chicago architects were now faced with was the challenge to reintroducing this technique following the 1871/74 fires into the exterior of a skyscraper while fireproofing the iron members.  Apparently, Boyington had been the first to accomplish this in Chicago in the Trading Floor of the Board of Trade by encasing the iron columns with brick and stone.

As the erection of the iron columns in the Board of Trade was underway, the threat of the impending height limitation produced a building permit for the Chicago Opera House Block, the second of the large buildings granted a building permit during the first week March 1884.  Plans for the project were first revealed in January, but the threat of the height limit had forced the project’s investors to secure a permit before the design had been completed.  The site chosen by the investors, a joint stock company led by Charles Henrotin, one of the founders of the Chicago Stock Exchange, and real estate magnate William D. Kerfoot, the southwest corner of Clark and Washington had been obtained through a lease from Ferdinand Peck.  The site was where the original extension of the old Chamber of Commerce was to have been built in 1880, until the Board of Trade decided to erect its own building on Jackson.  As was the case with the Central Music Hall, the site they had chosen to build on was ideal as it was served by all three of the city’s cable car lines.

Map of the Loop, 1884. (Author’s collection)

Their timing was intimately connected with the final completion of the new Cook County/City Hall scheduled for completion in January 1885.  This lot across the street from City Hall would provide convenient access for those who needed an office close to the city’s leaders who would be finally moving from their “temporary” post-fire location in the south back to their traditional location on the courthouse square in the “north end” of the business district.  Such market potential led the Opera House’s leaders to select this site because, as had been the case with Central Music Hall, the inclusion of office space was still an economic necessity for the financial support of an auditorium of this size in Chicago’s business district.  I will discuss the events that led up to and the reasons for the erection of a new opera house in Chicago in the next chapter, one of these being the inadequacy of the four-year old Central Music Hall located only two blocks to the east.  


If we are to believe Louis Sullivan’s claim in his Autobiography of an Idea (p. 287-89), that in the early eighteen eighties Adler & Sullivan were equal in reputation and practice to Burnham & Root, than one would have thought that this project that incorporated a large auditorium in addition to a ten-story skyscraper would have been made in heaven for Adler & Sullivan.  But Sullivan’s claim was disingenuous for although Adler & Sullivan had by this time, in addition to the Central Music Hall and the remodeling of the Exposition Building for the Chicago Music Festival, also completed the successful remodeling/updating of three of Chicago’s largest theaters, and were at this precise moment engaged in remodeling a fourth, (that we will review in the next chapter), and Sullivan had also begun to make a name for himself as a designer of interior ornamentation by early 1884, they had yet to design a tall speculative office building, contrary to Sullivan’s assertion late in life. (Their first commission to design a skyscraper, the Wainwright Building in St. Louis, was still over six years in the future.)  Instead, Henrotin and Kerfoot commissioned the relatively inexperienced, but as we will learn, “well-connected” firm of Henry I. Cobb and Charles S. Frost, who had never designed a performance space to design what was planned to be Chicago’s largest auditorium.  

Peabody & Stearns (George A. Fuller), United Bank Building, New York, 1880. (Online)

Henry Ives Cobb had been born into a Boston patrician family in 1859.  He had studied civil engineering at Harvard and architecture and mechanical engineering at MIT.  He had then been hired in 1880 by the local firm, Peabody & Stearns, where he befriended Charles Sumner Frost, who had also studied architecture at MIT.  Cobb’s older brother Albert had moved to Chicago a number of years earlier, where he had joined the ranks of Chicago’s northside “upper crust” (that included Potter Palmer, Charles Henrotin, and William Kerfoot) in the city’s Union Club.  In September 1881, Albert informed his brother back home that the club was sponsoring a design competition for a new building to be erected across from Washington Square.  The club’s members had been goaded into erecting a new building by the southside’s Calumet Club (that included Marshall Field, Philip Armour, and George Pullman) who had recently announced that it was going to build a new building designed by Burnham & Root (see Sec. 6.9).  The twenty-two year-old Cobb had submitted a Richardsonesque design that managed to be picked by the competition committee in December 1881 over one by Root that had been the early favorite.  (Cobb, in addition to his brother, may also have had a leg up on the competition as his former Peabody & Stearns associate, George A. Fuller, who had designed and supervised the construction of the recently completed Union Club building in New York on 39th St., had already moved to Chicago the previous year in search of “greener fields.”)

Peabody & Stearns (George A. Fuller), Union League Club, New York, 1879. (Online)
Burnham & Root, Calumet Club Building, Chicago, NE corner of Michigan Ave. and 20th St.,1881. (Lowe, Chicago Interiors)

Chicago’s architectural history was about to receive another influence from Boston (adding to the effects that the Brooks brothers and H.H. Richardson were having on the city’s buildings in addition to the effects that the railroads owned by Bostonians were having on the city’s urban structure). I listed Fuller first in the title because I think he had a greater immediate impact on Chicago’s architecture than did Cobb & Frost. I last discussed Fuller in Sec. 5.12. where as Peabody & Stearns’ partner in charge of their New York office, he had just finished putting the final touches on the United Bank Building. Our interest in Fuller is that he was an early advocate for the use of steel in building construction that was evidenced by his use of exposed iron columns in the storefronts of the Bank building.

George Fuller, United Bank Building. Detail of iron columns used in the storefront along Wall Street. The iron column is visible immediately to the left of the telegraph pole. Note that he did not repeat this detail on the wall to the left. (Online)

Fuller had been born in 1851 in nearby Worcester, MA, and had learned construction “in the field” before he briefly had some architectural training at MIT, then commonly referred to as “Boston Tech,” prior to his finding a post with Peabody & Stearns in 1872. He was known as having a natural instinct with construction-related issues. Actually, Fuller was the senior of the three, being five years older than Frost and eight years older than Cobb. Fuller left New York in late 1880 to form a firm with another former Bostonian who had already relocated to Chicago, C. Everett Clark Fuller to form Clark & Fuller.  

Cobb & Frost, Union Club, southwest corner of Dearborn and Washington Place, 1881. (Wolner, Cobb)

Having won the Chicago Union Club competition, Cobb decided to cast his lot with Chicago and moved there in early 1882, having convinced his friend Frost to join him in a new firm.  They then arranged that Fuller should have the construction contract for the Club. Cobb followed his brother’s lead in joining the Union Club, where, within three months he had bagged one of the city’s most prestigious and expensive commissions, Potter and Bertha Palmer’s new mansion on Lake Shore Drive.


Palmer, who had become the city’s wealthiest man following the death of William Ogden in 1877, had hired Cobb & Frost to design his new mansion that was to be located in what Palmer had secretly planned to make the city’s newest fashionable residential area, Lake Shore Drive on the North Side of the river.  As he had done some twenty years earlier with moving the city’s prime retail area from Lake to State Street, Palmer now planned to pull off a similar real estate coup by moving Chicago’s high society from Prairie Avenue on the South Side to Lake Shore Drive in the north.  (This was not as radical as some historians make it out to be, as I have shown that many of Chicago’s elite, such as Ogden and his associates, had always resided in the North Division since the founding of the city.)  Over the period that stretched from 1875, when the North Parks commissioners had first laid out Lake Shore Drive as a carriageway to link downtown to Lincoln Park, until the newspapers broke the story in April 1882, while Palmer and his wife resided in the Palmer House, he was quietly purchasing lots, in a manner similar to how he had bought State Street: along the planned thoroughfare, assembling a two-block wide strip of real estate along the lake that ran from Lincoln Park south to Bellevue Place.

View looking south down Lake Shore Drive, from Burton Place. ca. 1890. (Wolner, Cobb)

These properties had the same view and access to Lake Michigan as did Michigan and Prairie Avenues in the south, with one important exception: no trains would disturb the peace or spoil the view from these new lakefront palaces, because Ogden, whose house had been east of the North Branch, had built the C&NW tracks to Wisconsin to the west of the North Branch of the river.

Cobb & Frost, Potter Palmer Residence, Lake Shore Drive, between Schiller and Banks, 1882. (Wolner, Cobb)

Cobb & Frost provided, with obvious “assistance” from their clients, a design for the block on Lake Shore Drive between Schiller, Banks, and Astor, in the style they called Normanesque and “English battlements style.” Like the Palmer House, the mansion’s design, inside and out, reflected the Palmers’ association with “good taste” with copious consumption, or to put it bluntly, “the more, the better.” (I used the term “parvenu” earlier when I discussed Palmer’s similar choice of materials in the second Palmer House: see Vol. One.) While one could explain the exterior within the context of Chicago’s growing class conflict, as providing good defense for its defenders with the crenellations ringing the building’s perimeter, the interior in which each room was thoroughly decorated in a different style, simply expressed the fact that the city’s wealthiest couple had enough money to do this. (I have to believe that this house was a direct response to the new William K. Vanderbilt mansion along Vanderbilt row on Fifth Avenue. Alva Vanderbilt, the new fashion-setter in New York and Newport, whom it is obvious that Bertha Palmer saw as her equal, had spent over $3 million in recently completing the most expensive house to date in the country.  For comparison, Potter Palmer had lavished $3.2 million constructing the post-fire Palmer House hotel.  I will review this project in the next chapter.)

Richard Morris Hunt, William K. Vanderbilt residence, New York, 1879. (Online)


Siry, Joseph M. The Chicago Auditorium Building. Chicago: University of Chicago Press, 2002.

Wolner, Edward W., Henry Ives Cobb’s Chicago, Chicago: University of Chicago Press, 2011.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Statue of Liberty under construction in Paris, 1883, Génie Civil, 1883. First Image of the structure of the Statue of Liberty reprinted in the American Press, American Architect, September 1883. (Loyrette, Eiffel)

When Eiffel was called upon by Bartholdi in early 1880, he had been deeply engaged in the design and the start-up of site construction for the Garabit bridge, but he immediately recognized the potential publicity that he could garner from being involved in such an international project.  Eiffel’s experience was such that he would fundamentally change Viollet-le-Duc’s intended structure.  He replaced Viollet-le-Duc’s mass with geometric stiffness by simply inserting an iron pylon, similar to those that he was designing for the Garabit Bridge, into the inside of the hollow sculpture.  

The 92′ tall central spine or pylon upon which the copper skin of the statue would be hung consisted of four columns made of riveted (laminated) wrought iron plates.  These were connected with diagonal bracing that gave the pylon its stiffness against the wind.  A secondary system of wrought iron braces was built from the pylon that roughly estimated the actual shape of the sculpture.  This system’s role was to support each copper plate independent of the others, primarily to avoid the accumulation of the weight from the plates above, and to permit thermal movement in the copper to freely occur so that the statue would not tear itself apart as the seasons changed from summer expansion to winter contraction.  Each copper plate was, therefore, joined to the secondary braces by a system of custom-fitted iron straps, that were not directly attached to the copper plates, but were slotted into copper sheathes that were riveted to the copper plates, again to allow each metal to move independent of the other. In the Statue of Liberty, Eiffel had reworked James Bogardus’ technique of using an iron frame to support its masonry curtain wall in order to support Bartholdi’s copper curtain wall. The point here is that sheathing an iron frame in a non-loadbearing envelope (be it masonry or metal or glass-the cast iron front) had been in use since 1855 (earlier if we count the cast iron front).  It would be up to American architects to apply this concept to the exterior of a skyscraper.

Gustave Eiffel, Iron Structure of the Statue of Liberty, 1880. (Trachtenberg, Statue of Liberty)

Typical of Eiffel’s precision, the statue was first erected piece by piece to make sure everything fit like a glove, at the Monduit workshop in Paris where the copper plates were being fabricated. Erection of the iron pier began in October 1881, which meant that the iron, more than likely, was fabricated by Eiffel prior to the start of his fabricating the iron for the Garabit project.  By December 1882, the construction had reached a height that it was visible above the rooftops of the neighboring houses in Paris.  Meanwhile, the hand and torch in New York were disassembled, packed, and shipped back to Paris.  By January 1884, Lady Liberty could be seen from all over Paris where she spent the summer sunning herself. 


Loyrette, Henri. Gustave Eiffel. New York: Rizzoli, 1985.

Trachtenburg, Marvin. The Statue of Liberty. New York: Penguin, 1977.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Statue of Liberty under construction in Paris, 1883, Génie Civil, 1883. First Image of the structure of the Statue of Liberty reprinted in the American Press, American Architect, September 1883. (Loyrette, Eiffel)

By 1883, the iron construction community in France (remember it had been Henri-Jules Borie who in 1865 had proposed the first design for a skyscraper (his Aérodômes – see Sec. 2.1.), had rebounded from the political and economic turmoil brought on by the Franco-Prussian War and the corresponding Paris Commune. Only the month before the first report of the use of iron columns in the Board of Trade, the September 1883 issue of American Architect had published the first image of the Statue of Liberty under a trial construction in Paris. We last discussed Bartholdi’s great project with its head on display at the 1878 Paris World’s Fair (See Vol. Two, Section 5.6) while its torch had been moved from Philadelphia after the World’s Fair had closed to its intended home, New York, and was re-erected in Madison Square Park, hoping to elicit donations to pay for its base (while the French were giving the statue, America was responsible for paying for and erecting the masonry pedestal). Then the roof seemingly had fallen in with the death of the project’s engineer, Eugène Viollet-le-Duc on September 17, 1879.  This had left Bartholdi in search of an engineer who had the knowledge and experience in the erection of large structures to help him complete the project.  

In Third Republic France in 1880, there were two experts in contemporary iron construction that Bartholdi could turn to: Armand Moisant (see Vol. Two, Sec. 6.10): the engineer for the Bon Marché complex that was still being completed and the Menier Chocolate factory, or Gustave Eiffel:

“Our builders of this age, which is justly styled the age of steel and iron, have so thoroughly learned to take into account of the resistances of these metals, that in very truth there seems no conception, however, grandiose it may be, before which they recoil…

“For a long time Americans have held the first rank in these bold experiments, which characterize the studies of that genius which pleases itself in pushing to its extremest limit the resistance of metals’ but rivalry has sprung up… It is thus that we have seen valleys, which had formerly been reputed inbridgeable, crossed by a single elegant arch, as in the case of the Duoro and Garabit bridges.  It is thus that we stood wonder-struck before the gigantic iron skeleton of the statue of Liberty Enlightening the World, offered by France to the United States, which surpasses in dimensions the famous colossi of antiquity.

While Viollet-le-duc had gained his knowledge in the restoration of medieval stone structures, both Moisant and Eiffel had learned how to build in iron first by erecting, and then by designing structures for railroads.  Whereas Moisant had gone on to become the leading fabricator of iron structures in France, his expertise centered around longspan, horizontal roofs, Eiffel had made a reputation in precisely calculated and fabricated, lightweight iron structures, that could be shipped anywhere in the world.  In addition to this expertise, Eiffel had built a number of vertical towers to support his bridges, which, more than likely, recommended him to Bartholdi’s project.  As such, the Statue of Liberty, with the change of its engineer during its design, would represent a benchmark in the history of construction, and, as we will see, also in architecture.  The generation who had grown up with masonry structures and had experimented with iron construction was handing the torch (literally) to the next generation who had grown up with iron structures.

Jules Saulnier and Armand Moisant, Menier Chocolate Factory, Noisel, 1869. A five-story building framed only in iron. (web)

Gustave Eiffel had graduated from the École Centrale des Arts et Manufactures in 1855 (a year before Jenney had graduated in Civil Engineering) with a degree in Chemistry (four years before Moisant had graduated in Civil Engineering), but soon discovered his true talents lay in the area of construction and structural engineering.  After receiving his diploma, he had worked his way up designing iron bridges for railroads and managing their construction.  In many ways, his talents and interests were focused more on construction, or what in America is known as contracting, rather than on the actual engineering of a structure.  In late 1866, paralleling Moisant’s efforts almost exactly, he was ready to strike out on his own, and borrowed the money to buy his own fabricating workshop in Paris, to allow him to offer a complete bid package of engineering design and contracting services.  On December 4, he began to advertise as “Gustave Eiffel, builder…[of] iron constructions, market halls… and in general all metal constructions.” Two years later, he formed G. Eiffel et Compagnie, a partnership with a young German graduate of École Centrale, Théophile Seyrig.  

Seyrig was a very gifted engineer, who freed Eiffel to concentrate on the construction and business side of the company, which Seyrig, being somewhat wealthy, had also helped to initially capitalize with an investment of 126,000 francs.  For the next ten years, Eiffel built up the business and his reputation of being an engineer known for the precise fabrication of iron structures and constructing a project on time and on budget.  During the economic downturn following the Commune, he had continued to hone his skills with foreign contracts.  There are two significant projects of his (both were mentioned in the above quote) prior to the Statue of Liberty that we need to review in order to appreciate who this engineer had become at the time Bartholdi approached him for his assistance.


Gustave Eiffel, Maria Pia Bridge over the River Duoro, Oporto, Portugal, 1875. Note the tapered vertical pylons. (Loyrette, Eiffel)

As we have seen so often in the nineteenth century, the railroad would also play a major role in the development of Eiffel’s reputation.  In early 1875, the Portuguese National Railroad Company advertised a competition for the design of an arched railroad bridge over the gorge of the River Douro at Oporto, Portugal.  The competition program required a clear span over the river of 525’ at the height of some 203’ above the river.  The arched span would be longer than the current record of 520’, held by the Eads Bridge over the Mississippi River at St. Louis, designed and fabricated by local engineer James B. Eads, that had been completely only the year before.  Eiffel’s design and bid was chosen as it was significantly less expensive than the other three finalists.  The design called for the railroad trestle to be supported over the river by a two-hinged arch and by intermediate iron piers on the slope from the river’s shore to the top of the gorge.  While the form of the arch is the more interesting of the two types of supports as it varies in width and depth directly in response to the loads it resists, it is the iron piers that are central to this study.  The tallest pier was 135′ tall, and Eiffel had also determined its profile strictly through an analysis of the loads to which it would be subjected.  Construction began in January 1876 and was completed on October 31, 1877.  It would be Seyrig, however, the more theoretical of the two partners, who would use the completed structure to throw the gauntlet down at the aesthetic traditionalists within France’s architectural community (many of which had been supporters of Louis-Napoleon’s Second Empire), by stating in his final report that the bridge’s true significance was aesthetic, and not just structural.  He stressed that the beauty of the final design had made no “architectural concessions of traditional ornamental beauty” (there was no traditional decoration placed on the bridge) but was completely due to the art of the “innovative” engineer:

“The arch form has always been considered the most elegant…Its construction, using a small number of large elements, gives the impression of robustness and power, while the whole retains the lightness imparted to it by the use of metal.”

The mounting intrusion of science (technology and industry) into the traditional realm of the architect would only generate an increased reactionary resistance among the French architectural community to the use of exposed iron in Paris’ buildings during the Third Republic.

The success of the Douro Bridge so impressed the French company that operated the railroads in the Massif Central region, that when it began projecting a line that would have to cross the deep gorge of the River Truyère at Garabit, it suspended the usual contracting procedures and instead of requesting bids, simply opened direct discussions with Eiffel:

“because only Monsieur Eiffel has constructed a similar work, and only he has the experience of the new assembly methods of which he is in large part the inventor, and for which he also has the equipment which was used to erect the bridge over the Douro… It would in any case be unjust to entrust the work to any other than Monsieur Eiffel, since it is his Douro bridge which gave the Engineers the idea of crossing the Truyère valley with a new route.

Eiffel proposed a design very similar to his Duoro Bridge.  The gorge of the River Truyère was over 400′ deep, which meant that the new structure was going to have to be twice as tall as was the Portuguese bridge.  Eiffel began to show his ego in being able to build larger structures than had ever been built in a rendering the company did for publicity:

“To give an idea of this height of 122 meters, we need only say that it is considerably greater than that of the towers of Notre-Dame and the column in the Place Vendôme one on top of the other.

Gustave Eiffel, Garabit Viaduct, 1879. Note his drawing of Notre-Dame with the Vendôme column perched on top for comparison. (Loyrete, Eiffel)

After Eiffel had signed the contract on June 14, 1879, he broke his contract with Seyrig, his partner and primary engineer, over a dispute about how much credit in public each of them should get for the company’s unique solutions.  Eiffel replaced Seyrig with a young, Alsatian engineer, Maurice Koechlin, who became the lead design engineer for the bridge.  Because of the greater height of the project, the main arch’s span grew to 607’, and the tallest iron pier  topped off at a height of 200.’  Site work began in January 1880, iron erection commenced in August 1882, and was completed in late 1884.

Eiffel, Garabit Viaduct under construction. (Loyrete, Eiffel)


Loyrette, Henri. Gustave Eiffel. New York: Rizzoli, 1985.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)


Burnham & Root, Rialto Building. Demolition photo showing the extent of iron framing, 1941. (Chicagology.com)

While the exterior of the Insurance Exchange broke new ground in Root’s maturing aesthetic understanding, the interior construction was still locked in the past.  As was done in the Grannis Block, an interior iron cage supported wood floor joists that were “fireproofed” with terra cotta tiles. This decision must have been a bow to economics, for Burnham & Root had not only incorporated hollow tile floor arches in the Montauk Block, but they also were also experimenting at this time with improved construction techniques in the design of the Rialto Building.  As early as March 1883, it had been reported that the owners of the Rialto had engaged the services of Normand S. Patton, an architect/engineer who had become well-versed in iron construction while working in the office of the nation’s Supervising Architect in Washington, D.C.  Patton (1852-1915) had been born and grown up in Hartford, CT, earning a BA at Amherst College in 1873, prior to his move to Chicago where he found employment in Jenney’s office (roughly paralleling Sullivan’s brief employment).  In the depths of the Depression in 1876 he had moved to Washington, D.C., until he accepted the call to return to Chicago.  The time spent in Jenney’s office was well before Jenney’s design of the First Leiter Building of 1879, meaning that Patton had become experienced with iron construction after he had left Jenney.

James Bogardus, McCullough Shot Tower, New York, 1855. (Silver, Lost New York)
James Bogardus, Santa Catalina Warehouse, Havana, 1858. The brick walls are built on the iron frame. (Gayle, Bogardus)

The Inland Architect of March 1883 reported that he had been called “to Chicago to take charge of the iron construction and act as consulting engineer [with Burnham & Root] upon the [Rialto Building].”  The importance of such expertise coming to Chicago at this particular time was not lost on the Inland Architect: “Mr. Patton has enjoyed exceptional advantages in the study of iron architecture and now, upon the eve of an era of iron and fireproof construction, his accession is a valuable one to the craft in Chicago.”  The extent of the use of iron planned for the Rialto in 1883 is not known, other than its sheer size alone would have made his experience valuable to Root. 

Cast iron columns after the 1871 fire. (Kogan and Wendt, Chicago)

The importation of Patton’s experience with iron construction, however, did not mean that iron had not been utilized in Chicago’s buildings prior to his arrival in early 1883.  Far from it: in Volume One I documented James Bogardus and Daniel Badger’s development in New York of the iron skeleton frame enclosed with masonry panels. Central to this development was the invention and perfection of the cast iron front, the first use of iron skeleton framing in the exteriors of American buildings.  In Volume Two, we saw how the 1871 Chicago and 1872 Boston fires destroyed the myth of the fireproof nature of the unprotected cast iron column and beam. Then the 1874 Chicago fire had forced the nation’s fire insurance companies to pursue the complete prohibition of iron framing in buildings that resulted in Peter B. Wight’s invention of terra cotta fireproofing.  

Meanwhile, the potential threat to iron framing had not stopped architects and engineers from continuing to refine the technique of iron framing for the interiors of buildings nor from experimenting its use for very tall towers.

David Reeves, Proposed 1000’ Iron Tower for the 1876 World’s Fair, Philadelphia, 1873. (Architectural Record, April 1959)

While iron framing in the exteriors of buildings had been for all practical purposes banned, Wight’s fireproofing technique of interior iron framing was slowly adopted and successfully used in all of Chicago’s tall office buildings erected in the early 1880s.  This type of construction I labeled “boxed” construction: a masonry box was constructed around the building’s exterior within which were erected the iron columns and beams.  Windows in the brick box were detailed either as holes built into the walls or the brick box was detailed as a series of piers linked by masonry spandrels.

Burnham & Root. The Rialto (left) as an example of pier-and-spandrel detailing and the Insurance Exchange (right) showing its wall-with-windows detailing. (Hoffmann, Root)

Therefore, the independent iron frame with a masonry curtain wall had been in service in the U.S. for some twenty-five years following Bogardus’ shot tower of 1855.  George Post had led the way in New York in his detailing of the exterior lightcourts in the Equitable (1867), the New York Produce Exchange (1880), and the Mills Building (1881). Chicago did not invent iron skeleton framing. The iron frame in 1883, therefore, was not, by any means an unknown technique waiting to be “invented” as many historians have claimed; by this date it was a well-developed system of construction. 

Post, Produce Exchange, 1880. Photo of Construction showing the iron skeleton framing in the lightcourt walls. (Landau and Condit, New York)

Meanwhile in Chicago, William Le Baron Jenney in his First Leiter Building of 1879 had inserted iron sections against the interior faces of the masonry piers to take the floor loads off of the piers. Jenney’s rather ad hoc detailing, however, did not catch on nor was reused in Chicago.

Jenney, First Leiter Building, 1879. Above: Construction Detail of Masonry Spandrel and Pier. Note that the iron spandrel beams have a bearing plate that transfers their load to the masonry, not the iron pilaster. Jenney used a pair of plates to connect the webs of the spandrels at either side of the pier to gain some continuity through the joint. Below: Sectional Elevation of Ironwork in Monroe Street Facade. Note three details: first, the spandrels bear on the masonry (as detailed above); second, the iron mullions are continuous, i.e., loadbearing to the foundation; and third, there are no iron sections in the masonry piers. (Art Institute of Chicago)

Meanwhile, within a year, S.S. Beman had designed the 195’ tall Water Tower for the Town of Pullman in 1880 using 100’ long iron columns fabricated by N.S. Bouton and George Pullman’s Union Foundry and Pullman Car-Wheel Works. By this date, iron construction was being given more exposure in Chicago’s architectural press.  

S. S. Beman, Pullman Water Tower, 1880. Section, Elevation. The 100′ tall iron columns that support the 500,000 gal. tank. (Online)

Across the street from the Montauk Block, then under construction, Haverly’s Theater was being erected.  Although the exterior consisted of solid brick walls, the supports of the galleries were all iron, leading Real Estate and Building Journal in July 1881 to state: “It is possible and feasible to construct the auditorium entirely of a light iron framework, which would make it practically fireproof, and every theater should be built this way.”  

Peter B. Wight, Fireproofed wrought iron Phoenix columns in the Chicago Board of Trade Tower, 1883. (Brickbuilder, August 1897)

Then in 1883, the same company that manufactured the iron columns for the Pullman Tower, had also fabricated the 90’ high, 12-sectioned Phoenix wrought iron columns, once again fireproofed with Wight’s terra cotta casings for the Board of Trade’s great tower.  Large wrought iron columns were also used in the Board of Trade to support the iron trusses that spanned the Trading Floor: “the outside walls will be surrounded with large, full columns placed between the windows, and they will largely support the upper stories.” Patton may have played a role in the design of these iron members, for he had been brought to Chicago in early 1883 to help with the iron construction in the adjacent Rialto project, a period that parallels the design of the Board of Trade.  The first report of the large iron columns in the Board of Trade appeared in October 1883, with construction lasting from December 1883 to August 1884. The photographs below suggest that the iron columns were fireproofed by being encased in brick and stone.

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H.H. Richardson: Left: Trinity Church, Boston, 1872; Right: All Saints Cathedral, Albany, 1883. (Van Rensselaer, Richardson)

Root’s design for the Santa Fe Building in Topeka (see last post) revealed that he was closely studying the latest “Romanesque Revival” designs from the East.  In addition to Peabody & Stearns’ R.H. White store, he would have seen H.H. Richardson’s latest designs published in American Architect during the second half of 1883.  I believe the project that had the most impact on him was Richardson’s competition entry for the Albany Cathedral.  The detail that got his attention, I believe, was the attached turrets that Richardson had placed on all four corners of the central tower. These reappeared on Richardson’s competition entry for the Allegheny County Courthouse that was named the winner on January 31, 1884. 

H.H. Richardson, Allegheny County Courthouse, Pittsburgh, 1883. (Van Rensselaer, Richardson)

This detail accomplished two design ideas. First, by rounding the corner, it emphasized the building’s three-dimensional mass, rather than how a sharp corner accentuated the surface plane of the wall. Second, as especially evident in the Pittsburgh tower, it imparted a distinctly vertical accent to the building, something that would greatly assist the design of this growing typology.  I do not know whether or not Root had seen the Courthouse drawings prior to March 1884 when Burnham & Root received the commission for a 10-story office building for the southwest corner of La Salle and Adams, but this building, the Insurance Exchange, would start a series of skyscrapers by Root that would sprout such turrets at the corners of their roofs. (Root would continue to use rounded elements to turn his corners such as in the Women’s Temple and the Ashland Block.)

John Wellborn Root, Comparative Study of Five Skyscraper Elevations, 1883-5. From left to right: Insurance Exchange, Phoenix, Rookery, 13-story version of Monadnock, Rialto. On the left are the designs in which Root experimented with the wall and single windows; on the right are the designs in which he experimented with piers and paired windows. The Rookery is best understood as Root’s synthesizing the best of each: a wall building with paired windows. (Kyle Campbell)

Let’s recall that when they received the commission for the Insurance Exchange in March 1884, Burnham & Root were already working on the Rialto Building, where Root had chosen the theme of the Rialto Bridge for the building with a corresponding Venetian Gothic concept that honored the work of John Ruskin.  The plan concept of the Rialto had been revised to where it finally comprised of two parallel double-loaded corridors linked by the elevator core forming an H-plan.  

Map of Loop, 1884. (Author’s collection)

With the Insurance Exchange (originally known by the name of its owner, Col. J. Mason Loomis), Burnham & Root were presented with the design of a long (165′) street front along La Salle at THE intersection of THE two most important streets in downtown Chicago during the 1880s, and, of course, directly opposite from “The Rookery,” the post-fire temporary City Hall. 

Burnham & Root. Left: Insurance Exchange; Right: Rialto Building. Note that both buildings have a projected oriel bay from the circulation corridor, in which, I assume, was located a circular stair similar to The Rookery. (Rand-McNally Views)

The lot was very narrow (60′), leaving them no alternative but to line La Salle with a single-loaded office corridor, that turned the two corners with a double-loaded corridor, creating a shallow U-plan that left a small void in the center at the back of the lot as an exterior lightwell.  As he was redesigning the Rialto at this same time, Root also projected an oriel window once again into the lightwell of the Insurance Exchange to accommodate a circular stairway extending unbroken to the top of the building that would become the centerpiece of the building’s spatial experience. 

Cathedral of St. Cecelia, Albi, France, 1282-1480) (Online)

In contrast to the Venetian Gothic theme in the Rialto, however, it appears to me that Root found his inspiration in what was then the largest all-brick building in the world, the Cathedral of St. Cecilia in Albi, a large city in south central France. (This influence had been first suggested by Boston architect C.H. Blackall in an article he wrote on Chicago architecture published in the February 1888 issue of American Architect.) Although the church is made solely of bricks, its arches are both pointed and round, so its style is generally said to be “Southern” French Gothic with a hall church plan.  As both of these early skyscrapers by Root were inspired more by the Gothic than by the Romanesque, although he had deployed the round arch in the Insurance Exchange, I therefore chose the more inclusive term “Medieval Revival” to describe these two contemporary designs by Root.

Burnham and Root, Insurance Exchange Building, Chicago, 1884. (Hoffmann, Root)

In contrast to how he had designed the Rialto as a series of free-standing, sharp edged piers with a paired-window spacing, in the Insurance Exchange Root appears to have decided to show the many faces possible in a brick building.  There are no free-standing piers, however, it is one, solid box of brick within its surface he has either cut single (not paired) windows or placed mutistoried piers.  While the lower two-thirds of its body have sharp, angled corners, the upper two-plus stories were designed without a “corner”: he has located a turret at each corner, thereby allowing the brick surface to wrap around the corner without a crease, emphasizing this portion of the building’s plastic mass.  In essence, he appears to have been experimenting with these two diametrically-opposed methods of structuring and expressing a building in an exploration to discover which was most appropriate for this new building type.

Burnham & Root. Left: Rialto Building; Right: Insurance Exchange. They have the same overall composition except that the Insurance Exchange has the extra floor detailed as a “belt floor.” (Hoffmann, Root)

Nonetheless, he still used the same overall elevational concepts for both buildings. Horizontally, a centrally-positioned triumphal arched entry was marked with widened piers that extended to the roof; these were restated at each corner to frame the elevation.  In addition, these were needed to visually buttress the thrusts of the arcade in the Insurance Exchange, while the wider corner piers would also have been necessary to “cover” the thickness of the intersecting piers at each corner in the Rialto. Vertically, he reused the Rialto’s layering sequence of 2-2-4-1, except that he inserted the additional floor of the Insurance Exchange as a belt layer of segmental arches under the layer that contained the continuous four-story high piers (albeit these were halved by the unfortunate application of a floating capital at mid-height, seemingly a leftover from the Burlington Building).   This transitional layer appeared to be added by Root to serve both as a cornice to terminate the two-story colonnade in floors 3-4, and as a base for the four-story arcade in floors 6-9.  This transitional layer was detailed not as a series of piers, but a plane with the windows cut into it, thereby it read as a horizontal datum that interrupted the piers, preventing them from being read as being seven stories in height.  The transitional layer also reinforced the dominant horizontal accent of the elevation, emphatically restated in the buildings unbroken horizontal cornice.  The top floor was defined with a continuous line of brick corbelling as well as with a change in the spacing of its windows, similar to how he had detailed the top floor of the Rialto, so as to disrupt the potential reading of the continuous piers continuing into the top floor, so that this layer was a distinct horizontal layer, as was the belt layer.  In summary, in early 1884, Root was not yet ready to make his tall buildings “vertical.”

The first and second floors were grouped as a two-story arcade that Root used to make a transition between the ground floor’s Bedford stone piers and the cherry red St. Louis pressed brick walls above.  Instead of detailing this two-story base entirely in stone, however, Root allowed the brick to invade the base into the second story.  While this may have softened what had traditionally been a severe disjunction of materials in the exteriors of buildings of the period, the triumphal arch suffered from a split personality.  The large, two-story arched entrance portal was surmounted by twin three-story turrets from which a balcony was supported.  Root then used the upward insertion of the great arch to dislodge the central three bays of the belt layer up one story, thereby shortening the two central piers of the arcade by one story. A subtle, but very sophisticated detail.  Hindsight is 20-20, so this armchair architect thinks that if Root had made only the two stories of the arch in stone, not only would he have avoided the split materials of the entrance arch but would have also visually reinforced the upward thrust of the stories above the arch.

His virtuosity in detailing brick and terra cotta produced a variety of techniques that were skillfully blended into a richly-textured whole, that once again spoke of a knowledge of Furness’ detailing in Philadelphia (as had Root’s designs for the entrance gate of the Union Stockyards and the Grannis Block).  The arches in the second floor were silhouetted by a gridded infill, detailed not unlike that used by Richardson in similar locations.  While the windows in the “belt” layer were detailed with sharp edges, making the openings appear to have been chiseled into the brick, the edges of the other openings were plastically molded by details such as engaged ribs and quarter-rounded brick.  Root reserved his best brick detailing for the top floors with their continuous articulated courses of bricks with raked or recessed horizontal joints to once again silhouette the arches in these two floors. (A detail that is often mistakenly credited to having been developed by Wright.)   

One of the few compositional differences between the Rialto and the Insurance Exchange was Root’s elimination of the Rialto’s central roof pavilions, giving the Insurance Exchange a crisper, straight cornice that accentuated the building’s box-like form.  He did, however, restate the three-story tall turrets at the corners of the roof, that projected a full story above the cornice.  These turrets allowed the lines of brick in the cornice to wrap around the corner without a sharp edge, achieving a surface continuity that was strikingly in opposition to the surfaces of the rest of the building that were defined with a sharp edge at the corners.  In truth, here was Root at his finest in exploiting brick’s inherent androgynous quality operating between surface versus mass: it was a “both/and” building.  As a postscript to the question of Root’s finding inspiration in the Albi Cathedral, I made the pilgrimage there in 2010 and brought back these photos. You can make your own decision. (We will see Root mine this building’s details in a number of his later designs, such as the First Regiment’s Armory and the Monadnock Block.)

Left: Burnham & Root, Insurance Exchange; Right: Albi Cathedral complex, out building. (Left: Monroe, Root; Right: Author’s collection)


Hoffmann, Donald. The Architecture of John Wellborn Root. Baltimore: Johns Hopkins University Press, 1973.

Monroe, Harriet. John Wellborn Root; A Study of His Life and Work. Park Forest: Prairie School Press, 1966.

(If you have any questions or suggestions, please feel free to eMail me at: thearchitectureprofessor@gmail.com)