Cloud Gate, a public sculpture by Indian-born British artist Anish Kapoor, is the centerpiece of the plaza in Millennium Park in Chicago, Illinois.
Measuring 33 by 66 by 42 feet (10 by 20 by 13 m) and weighing 100 tons, the proposal featured a seamless, stainless steel surface inspired by liquid mercury. This mirror-like surface would reflect the Chicago skyline, but its elliptical shape would distort and twist the reflected image. As visitors walk around the structure, its surface acts like a fun-house mirror as it distorts their reflections.
Anish Kapoor's design proposal was chosen over works by 30 different artists. On the underside of the sculpture is the omphalos, an indentation whose mirrored surface provides multiple reflections of any subject situated beneath it. The apex of the omphalos is 27 feet (8.2 m) above the ground. The concave underside allows visitors to walk underneath to see the omphalos, and through its arch to the other side so that they view the entire structure.
The sculpture's weight raised concerns. Estimating the thickness of the steel needed to create the sculpture's desired aesthetics before fabrication was difficult. Cloud Gate was originally estimated to weigh 54 tons when completed. However, the final figure was almost twice as heavy. This extra weight required engineers to reconsider the sculpture's supporting structures. The roof of the Park Grill, upon which Cloud Gate sits, had to be built strong enough to bear the weight. The large retaining wall separating Chicago's Metra train tracks from the North Grant Park garage supports much of the weight of the sculpture and forms the back side of the restaurant. This wall, along with the rest of the garage's foundation, required additional bracing before the piece was erected. Cloud Gate is further buttressed by lateral members underneath the plaza that are anchored to the sculpture's interior structure by tie rods.
Being outside, concerns arose that it might retain and conduct heat in a way that would make it too hot to touch during the summer and so cold that one's tongue might stick to it during the winter. The extreme temperature variation between seasons was also feared to weaken the structure. Graffiti, bird droppings and fingerprints were also potential problems, as they would affect the aesthetics of the surface. The most pressing issue was the need to create a single seamless exterior for the external shell, a feat architect Norman Foster once believed to be nearly impossible.
The cost for the piece was first estimated at $6 million; this had escalated to $11.5 million by the time the park opened in 2004, with the final figure standing at $23 million in 2006. No public funds were involved; all funding came from donations from individuals and corporations. Kapoor's contract states that the constructed piece should be expected to survive for 1,000 years. The lower 6 feet (1.8 m) of Cloud Gate is wiped down twice a day by hand, while the entire sculpture is cleaned twice a year with 40 gallons (150 L) of liquid detergent. The daily cleanings use a Windex-like solution, while the semi-annual cleanings use Tide. In addition to the scheduled cleanings, the work endures periodic vandalism, including a notable February 2009 incident during which two names were etched in letters about 1 inch (25 mm) tall on the northeast side of the curved sculpture. The graffiti was removed by the same firm that did the original polishing.
Kapoor often speaks of removing both the signature of the artist from his works as well as any traces of their fabrication, or what he refers to as "traces of the hand". He aspires to make his works look like they have independent realities that he reveals rather than creates. For him, removing all the seams from Cloud Gate was necessary in order to make the sculpture seem as though it was "perfect" and ready-made. These effects increase the viewer's fascination with it and makes them wonder what it is and where it came from.
As is the case for all works of art currently covered by United States copyright law, the artist holds the copyright for the sculpture. This allows the public to freely photograph Cloud Gate, but permission from Kapoor or the City of Chicago (which has licensed the art) is required for any commercial reproductions of the photographs.
Condensed from Wikipedia