British Sculpture Could Fry Birds

March 7, 2001 -- It's a ground-breaking sculpture about to grace a playhouse in the British city of Nottingham. There's just one problem: for 16 weeks a year, it will barbecue birds that cross its path.

The sculpture, designed by Anish Kapoor, is made of a giant concave steel mirror, and is intended to reflect the sky. Unintentionally, it focuses the rays of the sun to such high intensity, birds flying through its path can be burned to death. Humans coming in contact with the light could be blinded.

Michael Merrifield, an astronomy professor at the University of Nottingham, a consultant on the project, said he warned the design team that the mirror, which acts like a magnifying glass, would focus the sun's rays so anything in its path could fry.

"It can focus a great deal of sunlight in a small area," Merrifield said. "You have to make sure the sun's rays never fall directly on the mirror. Any pigeons or birds that flew within the path of the mirror's reflected rays could potentially fry."

Sun Shades Will Block Rays

The threat would come mostly for 16 weeks of the year when the sun rises above the playhouse. The sculpture is in shade the rest of the year.

To combat the risk, sun shades will be placed on the playhouse roof until an exact and safe position can be set for the sculpture.

"A concave mirror acts like a magnifying glass and if you focus the sun's rays on it the temperatures reach thousands of degrees," Merrifield said.

The sculpture's project team director Alan Humberstone, said he was aware there was a potential problem from the start of the project.

"We waited until the exact position of the sculpture would be set," Humberstone said.

The historic building must now be granted permission by British heritage authorities to erect a sunscreen during the 16-week danger zone until a less obtrusive screen can be built.

"I am sure there are some people who don't mind if birds get killed but then this is a reasonable danger in general," Merrifield said.