In May 2021 the Art Institute of Chicago unveiled the Hartwell Memorial Window in the Henry Crown Gallery atop the Women’s Board Grand Staircase in the museum’s historic Michigan Avenue building (fig. 1).^[1] Designed by Agnes F. Northrop for Tiffany Studios, the sublime scene soars over twenty feet high and captures a mountain day’s end. Warm light emanates from the setting sun, catching on the rushing waves of the central waterfall and dancing through the trees—the transitory beauty of nature conveyed through an intricate arrangement of vibrantly colored glass.1

“It’s like it has always been here” is a phrase often heard from those familiar with the historic space, yet for more than one hundred years the window lived another life in a church in Providence, Rhode Island. When Art Institute staff began to work on acquiring and installing it at the museum, we strove to honor the historic integrity of the window as we developed a contemporary approach to its installation in an entirely new environment. Moving back and forth from past to present is the heart of curatorial and conservation work—we revisit the past in order to envision the future of objects of aesthetic and historic significance. When applied to the Hartwell Memorial Window, this process led to a novel approach to the care and installation of stained glass and revealed new insights and lines of inquiry into Tiffany Studios’ practices. Considerations of place were essential to the understanding of how the window was made, the circumstances of its original installation, and what its future would be at the Art Institute. This essay explores the creation, conservation, and display of the Hartwell Memorial Window, offering context and behind-the-scenes specifics on the collaborative, cross-temporal efforts to realize this unparalleled landscape in light.2

Origins of the Hartwell Memorial Window

In May 1916 the Building Committee of the Central Baptist Church in Providence, Rhode Island (now the Community Church of Providence), issued a pamphlet titled The New Edifice of the Central Baptist Church. The document laid out the goals and characteristics of the new building, a “Late Tudor Gothic” where “from every side the building presents an equally attractive appearance.” The materials listed include stone, concrete, steel, wood, copper, slate, terrazzo, and glass, specifically: “Pearl-white, heavily leaded, cathedral glass throughout. (Except as memorial windows may privately be provided.)”^[2] Blueprints of the architects’ plan for the building include a five-lancet window rising over the baptistry in the chancel (fig. 2), which would indeed be filled with a memorial window by the time the church held its opening dedication ceremony on April 15, 1917.^[3]3

Described at the time as “the largest landscape ever erected,” the Hartwell Memorial Window is still one of the largest and most complex stained-glass landscape scenes produced in America.^[4] Mary Hartwell commissioned the majestic window in the name of her late husband, Frederick Hartwell, an active member of the congregation for over fifty years who had also served as a deacon of the church until his death in 1911.^[5] To honor his memory, she turned to Tiffany Studios to produce the window for the church. Although to date there are no known business records among the church, the Hartwell family, and Tiffany Studios, existing archival materials, Hartwell family oral histories, and the window itself stand as a testament to their shared history and the tremendous impact of Mary Hartwell’s gift.4

Place does not only relate to where and how the window has been physically sited along its lifespan, it also shapes the subject matter of the Hartwell Memorial Window. The depicted landscape is a distant view of Mount Chocorua, one of the most beloved peaks of the White Mountains in New Hampshire, an area that held deeply personal significance to the Hartwell family. Frederick Hartwell was born in Langdon, New Hampshire, and even as he settled and built a full life in Providence, he maintained ties and property in his home state. According to the family, Frederick and Mary spent time together near Lake Winnipesaukee, later buying property with a great view of the White Mountains, where the two loved to watch the sun rise and set over the landscape (fig. 3).5

Their view, interestingly, was not of Mount Chocorua but largely of another famous peak in the same range: Mount Washington.^[6] It is rare to know the location depicted in a Tiffany Studios window, and, even more so, to have evidence of the likely exchange of ideas around how best to interpret it in stained glass for a religious space.^[7] Mount Chocorua was certainly better known than neighboring mountains and was a widely celebrated icon of the American landscape, made famous by the landscape paintings of Thomas Cole, Frederic Edwin Church, and John Frederick Kensett. Thus, it is revealing to consider the Hartwell Memorial Window as a composition inspired by a location with individualized significance yet ultimately representing an altered, idealized version of place: the peak of a better-known mountain close to the family home perfectly aligned with an imagined waterfall flowing down to the bottom of the scene (and, importantly, directly to the site within the church where baptisms are performed) (fig. 4).6

It is no surprise that Hartwell and the church turned to Tiffany Studios in New York to make this extraordinary window. By the time of the commission around 1917, Tiffany Studios was the preeminent American source for leaded glass windows, and their firm was synonymous with radiant materials and technical brilliance (figs. 5–7). Louis Comfort Tiffany opened his glass and decorating firm in 1885 to explore the possibilities of glass in his search for naturalistic beauty.^[8] The firm became known for “painting” with glass—that is, achieving spectacular color and textural effects in the molten medium itself rather than through applied surface treatments after cooling. To do this, Tiffany Studios produced, and in some cases sourced from other companies, a kaleidoscopic variety of glass types such as foliage glass, in which confetti-like shards of glass are fused to the batch glass, and streaky glass, where two or more colors swirl and twist in a single sheet.^[9] Tiffany artists often then stacked these different kinds of glass, building them up anywhere from two to five layers thick to achieve more precise or nuanced effects in transmitted light.7

The Hartwell Memorial Window, like all art made under the Tiffany name, represents the work of many hands. The window was designed by Agnes F. Northrop (1857–1953), the firm’s leading landscape window designer and the only woman known to be given responsibility for landscape imagery in leaded glass.^[10] Window compositions were conceived by one or more designers—in this case, Northrop—but there were specialists across the firm who worked on each phase of the conceptual and material development of the glass: experimenting with glass formulas, making different types of sheet and cast glass, selecting specific pieces for each project, cutting them to fit the design, and uniting the pieces with strips of lead or copper soldered together (fig. 8). The range of makers who collaborated on Tiffany Studios objects, largely misunderstood and long left out of scholarly and museological records, continues to come to light through research into the artists’ personal archives; no single archive of the firm exists, nor was it the practice to acknowledge individuals by way of marks or signatures.^[11]8

As for the Hartwell Memorial Window, the only documented record of its production is a passing statement captured in the church archive that elevates “Mr. Tiffany” alone as the designer: “In his interpretation, Mr. Tiffany avoided the use of scriptural figure, nor has he employed any paint or pigment with which to effect [sic] the delicate shading and modeling, the entire picture having been developed with Tiffany Favrile (American) glass which he makes subservient to his demands by manipulation; etching for reduction of tone and adding layers for intensification.” The description continues, “About eight months have been consumed by American artisans in the construction of this distinctly American window, which was on private view, and for Mr. Tiffany’s final criticism, for a few days before its shipment from New York.”^[12] Upon completion, the panels of glass were shipped from New York to Providence to be reassembled inside the church in time for the building’s dedication.9

While little is known of studio operations, even less is known about the personnel, communications, and decision-making hierarchy employed throughout the Hartwell Memorial Window’s installation phase. It would take one hundred years and a reconsideration of the window’s place in the world before these practices would come back into view—this time not through the archive, but through the object and its setting.  10

Considering a New Location

The Hartwell Memorial Window remained in the sanctuary of the Community Church of Providence until 2018, when the congregation decided to relocate the window to the Art Institute of Chicago where it could be conserved to ensure its long-term stability and remain on public view. Speaking on behalf of the congregation, Pastor Evan Howard explained, “We recognized the need to see the window cared for by specialists and experienced by a wide audience, and were impressed by the Art Institute’s dedication to educating, engaging, and inspiring visitors from all over the globe.”^[13]11

It was clear from the beginning that this was no ordinary acquisition—usually, when a museum accepts a work of art into its collection, it is immediately and physically transferable, not affixed to another building. Much preparatory work was needed to understand the window’s construction and the specifics of its integration into the original site in order to create the necessary conditions for its relocation and new display at the Art Institute.12

As a first step, curators and conservators assessed the window’s material and structural make-up. Although the window reads as a seamless whole, it is in fact comprised of forty-eight individual panels of heavily layered glass that is sometimes up to five layers thick (a panel being a section of layered glass held in place by a lead perimeter). The Hartwell Memorial Window incorporated an array of the firm’s most celebrated and unusual glass types supplemented by acid etching and resist techniques (figs. 9–12).13

Despite its age at the time of inspection, the window was deemed in remarkable condition with no major damage or losses to the glass. Its engagement with the surrounding cast-stone tracery was unusual in that the panels were notably smaller than the masonry openings, with a uniform gap of approximately one inch between the perimeter leads and the stone. The building had not been finished when the window was commissioned, and this sequencing may be responsible for the discrepancy. Unable to seat the window panels directly into the masonry grooves, the original installation team employed strips of wood to bridge the gaps, securing the glass to these wooden inserts with malleable lead tabs folded around and over the edge of the glass. The glass, in essence, “floated” within the setting (fig. 13). The assembled window was then given support across the front by inserting steel rods, known as saddle bars, into the adjacent stone and binding the glass to these by way of twisted copper wires, a method of installation employed since the Middle Ages. As a final step, a thick bead of lead glazing putty was applied to the interior perimeter of the glass both to cover the wood strips and lead tabs and to create a weather seal.^[14]14

From this physical examination, conservators determined that the window would need to be deinstalled from the interior. In the summer of 2018 a four-story scaffold was erected inside the church, and a skilled team of specialist stained glass conservators and technicians began the arduous and exacting work of clearing away layers of aged, hardened putty; cutting the copper tie wires; extracting the saddle bars; disengaging the panels from one another; and sending all forty-eight panels of glass down the scaffold. Once safely on the ground, each individual panel was secured within a custom housing, and the window left its original site—on the road yet again, this time traveling nearly one thousand miles to Chicago.15

The Hartwell Memorial Window in Chicago

 A New Design

There were enormous challenges to creating a new setting for the Hartwell Memorial Window. Not only did the museum need to consider the object’s sheer size, but it was also crucial to consider the shift from its original religious environment, in which it played a central role, to the museum, where it would live in proximity to objects from a variety of periods and places around the world. The result of the initial full-campus review was auspicious: the Hartwell Memorial Window would be installed in the gallery of the Woman’s Board Grand Staircase near the museum’s Michigan Avenue entrance. This part of the museum campus was originally constructed to open amid the fanfare of the 1893 World’s Columbian Exposition, where it was the site of the Parliament of the World’s Religions, considered the first organized interfaith congress.^[15] This new setting for the window would celebrate the artistic virtuosity of the work and, at the same time, honor its original installation in a hallowed architectural space.16

The location presented physical hurdles for design and installation. The window was now going to be sited against a solid wall that would not accommodate the creation of additional space for a lighting system. This meant the design needed to include a light source that, if not equivalent to its original source of illumination, was at least strong enough to transmit light through the darkest and heaviest passages of glass and accentuate the naturalistic details. No longer housed within the supporting framework of the church’s masonry, the glass would now require a structure capable of supporting a combined weight of nearly one thousand pounds. Additionally, the composition of the Hartwell Memorial Window needed to stay faithful to its original architectural context since the scale could not be reduced and still retain a legible scene. The proposed solution thus needed to replicate the stone tracery from the church in some form. Furthermore, the Art Institute team, having seen the original setting of the window firsthand, was committed to maintaining fidelity to the historic materials and installation practices as much as possible.17

Beyond these structural exigencies, a museum context demanded two additional requirements: each individual section of glass be removable without disturbing other sections, and lighting components be serviceable without having to move or otherwise disturb the glass. Perhaps most challenging of all, the gallery walkway is less than ten feet deep, which meant that all elements of the new setting needed to interconnect within a very shallow profile (one foot or less) in order to maximize space for visitors in front of the window. Simply put, there was no precedent for this endeavor.18

The solution materialized following extensive archival research into the building’s construction; numerous drawings and mock-ups; and field tests with colleagues in allied disciplines of structural engineering, laser scanning, fabrication and machining, lighting design and distribution, and mountmaking (fig. 14).^[16] The window would be set into a steel box-tubing frame that would tie into the building’s masonry. Behind the new frame, a track with a suspended LED lighting system would extend laterally on both sides of the window to allow for servicing. The stained glass panels themselves would be mounted into custom-cut aluminum plates bolted to the steel frame. Having anticipated the probable need to reproduce the decorative stone surround of its church setting, a laser scan of the empty tracery in the church was commissioned after the glass had been removed. Using the resultant digital point cloud, a decorative fascia was made from a high-density foam using a computerized manufacturing process called CNC machining; this fascia was then cleated to the steel structure.19

Fig. 14

As-built construction drawing of the Hartwell Memorial Window showing: (1) decorative fascia; (2) the structural support for the decorative fascia; (2) mount plates; (3) aluminum mounts and window panels; (4) light-emitting diode (LED) lighting system; and (5) structural frame supporting the lighting system and mounted glass. To select and transition between layers, click the image layer menu icon to the right of the slide bar.

The Many Facets of Housing the Glass

With these broad outlines in place, multiple processes were initiated—namely, offsite work on the support, lighting system, and fascia and on-site work at the Art Institute to conserve the glass and fabricate the mounts. The mounting methodology was to secure the glass to the back of aluminum mounting plates using custom brackets made from extruded aluminum Z-bar. All brackets and contact surfaces between the glass and the plates were cushioned with polyethylene foam attached with double-sided, pressure-sensitive tape. Despite the inherent simplicity and modularity of this system, the process was extremely labor intensive, requiring test fittings of each panel in its plate to determine bracket depth and placement as well as the amount of pressure that could safely be applied. Where required, Plexiglas shims were used to center the panels within their new openings to create a uniform and consistent reveal of their perimeter leads. Since the largest panels could only be handled in an upright position, it was necessary to fabricate a custom easel for support during the fittings of the largest units (fig. 15).20

One of the most daunting aspects of the process was reconciling the organic, handmade, and irregular nature of the window against the geometric, consistent, regularized, and computer-generated steel frame underlying the gothic decorative fascia. No two of the forty-eight panels that comprise the full scene are identical in shape, nor do they fit together at true angles. None of these idiosyncrasies were appreciable in the church where the window sat twenty-five feet in the air and each panel’s lead perimeter was hidden behind putty. The new setting, however, needed a different solution for these mismatches: a new bridge from glass to frame, which would now be perceptible at eye level. To arrive at a new “average” shape for the openings around the glass and the necessary width of the new aluminum plates, the Art Institute team used an elaborate reconciliation process based on tracings of each of the window’s forty-eight panels against rubbings taken of the architecture in situ at the church. These many variabilities meant that cutting each opening for the glass in the aluminum plates had to be done by hand rather than laser so that a fabricator could make judgements by eye.21

Next, the team considered how to support the glass panels within the aluminum mounts. Museum display of stained glass with piecing joints (in which an upper panel of glass physically engages with the one below by way of interlocking channels) typically takes one of two forms. One approach is to separate the panels from one another and house them independently in frames to structurally reinforce the perimeters and enable each panel to be handled and/or removed more easily. The result of this treatment, however, is added visual weight between the panels. Disrupting the seamless nature of the Hartwell Memorial Window’s composition was immediately deemed an unacceptable tradeoff. The second option is to maintain the functional use of saddle bars. In a museum context, however, it is often the case that saddle bars are affixed to the back of the glass regardless of whether they are original or replacements.22

Given the size of the Hartwell panels, especially those of the largest lancets, the support provided by saddle bars was essential, but the elaborate buildup of glass at the back precluded their use on the reverse: because the panels were mounted behind the aluminum plates, the saddle bars could not sit flush with the glass. The solution to this problem was to notch the aluminum mounting plates—permitting the saddle bars to rest directly against the glass—and engineer brackets that could receive and support the saddle bar from behind. The notches were covered by steel tabs affixed with set screws to lock the saddle bars in position. In this way, the saddle bars function exactly as they did in their original context, both structurally and aesthetically (fig. 16).23

Similarly, a novel mounting solution was needed along the window’s lower inscription panels. These panels appear below a series of large heavy trefoil panels, seemingly as one unit. In the church the bottom of the inscription panels rested on the masonry sill, and T-bars at the top served to support the trefoil panels over the inscription panels. To facilitate this same functionality in Chicago as in Providence, two notches were cut into the aluminum plate into which the T-bar could be inserted (fig. 17). Every saddle bar and T-bar was labeled during extraction, ensuring that these fixtures were returned to their rightful locations within the window in Chicago. Each of these solutions derived from the original setting in Providence, and it would not have been possible to find a way forward in 2021 without reference to the 1917 installation. It was a laudable achievement to completely reintegrate all of the moveable structural elements supporting the glass panels, not for decorative or aesthetic purposes but to serve as functional units that accord with the original setting in Providence.24

Lighting the Window

In Providence the window was sited with a northwest exposure, providing variable light transmission throughout the day that changed in intensity across the landscape. The prevailing conditions by turns left the densest panels obscured with the central lancet lit to best advantage or set the densest panels aflame while overexposing the central scene. The window’s destination in the Crown Gallery would not only require artificial illumination but also introduce a significant quantity of natural light competition from the expansive skylight above. Suddenly the window would have a great deal of light cast across the front of the panels rather than the back. The overarching imperative was thus to achieve the maximum possible brightness that current lighting technology could provide while also considering other factors like the extent to which the museum could control both lumen output (the total visible light) and color temperature (the color characteristics of a light source).25

After numerous tests, the team selected a system of adjustable, double-sided LED strips that created a light-grid behind the glass.^[17] Trials of color temperature made it clear that the darkest and most opaque passages of the glass were best viewed with a higher temperature (a cool white light). To avoid the individual diodes appearing as a network of bright dots, translucent acrylic sheets sit between the glass and the lighting system to diffuse the light. The result is a consistent output of light behind each panel that appears brighter or dimmer to the eye depending on the qualities of the glass, such as transparency, opacity, and the number of layers. Interestingly this solution created the inverse viewing conditions of those in the church: the window looks different throughout the day because of the natural light changing across the front of consistently backlit panels, as opposed to the sun’s trajectory behind the glass. As in Providence, the colors and contrasts of the window provide the visitor something new with each passing minute. 26

Conserving the Window

A full condition report of the panels after extraction confirmed that the window was in remarkable condition for its age but required a comprehensive cleaning of the front and back, consolidation of all extant glazing putty, and necessary glass repairs.^[18] During the course of treatment, several revelatory features emerged that prompted reconsideration of Mr. Tiffany’s claim to have never “employed any paint or pigment with which to effect the delicate shading and modeling.”^[19] Upon opening a small panel with a noticeable break, to great surprise, dots of a black material, possibly wax-based crayon, could be seen between two layers of plating (fig. 18).^[20] Because the lead perimeter around this panel was intact and showed no sign of any damage or previous conservation treatments, there is every reason to assume this addition was made during fabrication, when the window was being judged against a lighted easel. For whatever reason, this intervention was deemed necessary to clarify and reinforce details of the landscape and can thus be clearly understood as finessing under controlled studio conditions. What is most striking is that it appears in a minute area at the extreme uppermost portion of the composition. Such meticulous attention to detail stands as a testament to the firm’s hallmark exactitude and high standards.27

In another, larger panel, a section of glass had fractured in half and been joined with glazing putty.^[21] When this broken panel was extracted for repair, it became apparent that it had an oil-based cold paint (that is, paint applied to the finished sheet of glass) on both the interior and exterior (fig. 19).^[22] The painting on the interior surface corresponds to areas that were too transparent and needed some amount of shading, while the painting on the exterior was applied to represent the missing portion of the tree trunk within that panel. The glass used for this upper plating—a relatively clear glass with blue and lavender streaks—is markedly different from the rest of the glass in the panel and is the only place in the entire composition where this specific glass is used. The lead work around this zone is also distinct—torn and rough—and was reinforced by a brownish-red adhesive in a seemingly hasty application. Unlike the previous example, this cold painting points to a split-second, field-level response to an unforeseen circumstance that almost certainly occurred on site during the original installation or in transit from the studio to Providence.28

These differentiated applications of a black drawing medium and oil paint on the surface of the glass constitute the only known use of such alterations within a Tiffany Studios landscape.^[23] These conservation discoveries made at the Art Institute shine a spotlight on little-understood practices at Tiffany Studios a century earlier and the even more opaque conditions of installing Tiffany windows at locations across the country at that time. Under what circumstances was it deemed appropriate and/or necessary to use paint on the glass surface, even as the firm built their reputation on eschewing this practice? Who was onsite doing the arduous work of assembling these luminous puzzles within existing architecture? Who was consulted when things went wrong? What materials were brought onsite for these purposes? How were they sourced? Taking these inquiries back to the existing archival materials, there are some intriguing clues in the documentation of other Tiffany projects. A small group of rare surviving ledger books from the firm’s mosaic department references working hours and associated costs for “Chicago Men” and “Extra Help in Chicago” on the elaborate mosaic work for the historic department store Marshall Field’s, for instance.^[24] There is also reference to “Extra help in Wappingers Falls” for the Grinnell Memorial at Zion Episcopal Church.^[25] This suggests the company relied on contracted labor in various locations for projects. Was this also the approach in Providence? While these questions remain largely unanswered, the act of re-siting the Hartwell Memorial Window brings material revelations to the fore and encourages new avenues of investigation.29

Putting the Pieces Together Anew

Once conservation and the fabrication of the decorative fascia, lighting system, and steel frame were complete, installation of the glass began in March 2021. The difficulty in managing the sheer physicality of the window and the components necessary for its installation cannot be overstated. Finding areas within the museum of sufficient size to accommodate the footprint of the panels, their plates, and crates, as well as to carry out treatment, plate fabrication, preparation, and test fittings demanded adaptation and flexibility as teams spread into unorthodox spaces like hallways and empty galleries. Within the enclosure of the installation site itself, the narrow confines of the walkway presented additional challenges as the necessary tools and lifting equipment were moved in, while conservation-engineering solutions were needed to ensure the safety of both the objects and the operators.^[26] Navigating these constraints required careful planning to choreograph a precise workflow and establish an efficient order of operations, enabling the window to go up securely over the course of four weeks (fig. 20).30

Places Unknown

Place has multiple definitions, from the purely geographical—a location, “a particular position or point in space”—to the more complex, “the role played by or importance attached to someone or something in a particular context.”^[27] This latter definition invokes a more phenomenological concept of space wherein a wide range of connections between people and materials develops based on shared experiences around and within a particular setting. A definition such as this allows place to be free from the constraints of size or scale—fixed neither in time nor space—and to alter as its surroundings and as the people and cultures within it shift in response to new ideologies or technologies.^[28]31

Stained glass conservation itself occupies a particular place at the intersection between architectural preservation and object-based conservation—between tangible and intangible heritage, which together form what can be called the “spirit of place … the physical and the spiritual elements that give meaning, value, emotion and mystery to place.”^[29] On the one hand, stained glass is profoundly associated with a specific architectural context, a physical place, and is emphatically tangible.^[30] Objects in a museum, meanwhile, float free from their original settings and occupy a more liminal space in which other values and narratives can predominate. Within the heritage community there is increased dialogue about the intangible aspects of our built environment and, in particular, traditional craft skills and the experiences of makers in addition to the universal emotions and sense of awe objects can prompt, irrespective of location or temporal distance since their creation. This is a shift toward a more people-centered methodology, “to recover … the roots of human experience and that which has been forgotten in the modern world with its positivistic focus on the empirical.”^[31] Through this lens, the relocation of the Hartwell Memorial Window allowed for not only the conservation of its material form but also the revelation and transmission of historic craft techniques and practices. Indeed, the act of this re-siting is what spurred the innovative collaboration across time and place described in this essay. It makes possible a public space for sharing these discoveries; for highlighting the skills and achievements of Agnes F. Northrop and her Tiffany Studios contemporaries as well as a new generation of practitioners; and for Art Institute audiences to contemplate universal themes of human creativity, love, loss, and memory. It also suggests there are even more associated places unknown: archives to be discovered, maker and material histories to be recovered, and new knowledge to be forged as people encounter, study, and appreciate this object into the future.32

Banner image: Installation view of the Hartwell Memorial Window.33