Nearly five decades after its initial installation, Alexander Calder’s monumental sculpture in the Hart Senate Office Building is preparing to fully realize the artist’s original vision with the restoration of its kinetic "clouds." The work, comprising five angular "mountains" and two curved "clouds," occupies the building’s nine-story atrium in Washington, D.C., and is recognized as Calder’s only collaborative piece featuring both a stabile and a mobile element.
Calder, renowned for pioneering kinetic sculpture, was commissioned in 1976 to design the work during the construction of the Hart building, which houses the offices of about half of the U.S. Senate. The design intended for the sculptural clouds suspended above the mountains to move gently by motorized means. Calder adjusted the model of the piece during a November 1976 visit to Washington but died of a heart attack the following day. The artist’s estate permitted the project to proceed posthumously, making it unique among Calder’s works. However, funding delays and technical difficulties postponed its completion until 1986, when Senator Nicholas F. Brady secured $650,000 to finalize installation.
Problems with the sculpture’s motorized components emerged early, preventing the clouds from drifting as Calder had envisioned. By 1992, the clouds ceased moving altogether, and the piece was effectively incomplete until the clouds were removed in 2014 for restoration and redesign. Alexander S. C. Rower, Calder’s grandson and president of the Calder Foundation, has emphasized that the moving clouds are integral to defining the work as a true Calder sculpture.
The extensive restoration replaced the original aluminum cloud panels with thinner, stronger carbon fiber composites, enhancing safety below the installation. A newly engineered motor system is expected to restore the delicate movements later this year. The total project cost reached $12 million, considerably higher than the original outlay. Philanthropic support came from Jon and Kim Shirley, collectors and art patrons with a longstanding appreciation for Calder’s work.
The restoration process encountered multiple challenges, including delays within the Architect of the Capitol and the need for bipartisan Senate approval. Legislative changes in 2017 facilitated the acceptance of private donations for art conservation. A particular technical hurdle involved replicating Calder’s signature matte black paint, no longer commercially available. Maryland’s current Senator Angela Alsobrooks, prior to her Senate tenure, coordinated with the U.S. Army Research Laboratory to recreate the specific pigment, underscoring attention to artistic detail.
Supporters of the project, including Senators Chris Murphy, Amy Klobuchar, and James Lankford, have highlighted the sculpture’s symbolic resonance for lawmakers, portraying it as a metaphor for the Senate’s capacity to address formidable challenges. The restored installation is expected to embody the harmonious contrast between the heavy, immovable mountains and the dynamic, drifting clouds, a balance noted by the Shirleys as vital to the sculpture’s impact.
The Calder Foundation anticipates that with the clouds once again in motion, viewers will experience the full expressive intent of the sculpture, a testament to Calder’s enduring influence on modern art and public space.