The writings include the only Greek version of On Floating Bodies known to exist, and the only surviving ancient copies of The Method of Mechanical Theorems and the Stomachion.

In the treatises, the 3rd Century BC mathematician develops numerical descriptions of the real world.

"Archimedes was like no-one before him," says Will Noel, curator of manuscripts and rare books at the Walters Art Museum in Baltimore, Maryland and director of the imaging project.

"It just doesn't get any better than re-reading the mind of one of the greatest figures of Western civilisation."

'Eighth wonder'

Revealing Archimedes' writings presents a huge challenge to the imaging team.

The original texts were transcribed in the 10th Century by an anonymous scribe on to parchment.

Three centuries later a monk in Jerusalem called Johannes Myronas recycled the manuscript to create a palimpsest.

Palimpsesting involves scraping away the original text so the parchments can be used again. To create a book, the monk cut the pages in half and turned them sideways.

To create a book Myronas also used recycled pages from works by the 4th Century Orator Hyperides and other philosophical texts.

Mr Noel describes the palimpsest as "the eighth wonder of the world".

"You never get three unique palimpsested texts from the ancient world together in one book," he told the BBC News website. "That's just completely unheard of."

The monks filled the recycled pages with Greek Orthodox prayers.

Later, forgers in the 20th Century added gold paintings of religious imagery to try to boost the value of the tome.

The result was the near total obliteration of the original texts apart from faint traces of the ink used by the 10th Century Scribe.

Bright light

Previously the privately-owned palimpsest has been investigated using various optical and digital imaging techniques.

However, much of the text remained hidden behind paint and stains.

The researchers have now turned to a technique known as X-ray fluorescence to tease out the final details of the writings.

The method is used in may branches of science including geology and biology. It has previously been used by other researchers to decode ancient texts.

In August 2005 a team from Cornell University successfully deciphered a series of 2,000-year-old worn down stone inscriptions.

The X-rays are formed in a synchrotron - a particle accelerator that uses electrons travelling at close to the speed of light to generate powerful "synchrotron" light.

The light covers a wide range of the electromagnetic spectrum, including powerful X-rays, a million times more intense than a transmission X-ray used in medical imaging.

"In fluorescence it's like looking at the stars at night whereas in transmission it's like looking during the day," explains Dr Uwe Bergmann of the Stanford Synchrotron Radiation Lab in the US, where the work is being done.

The light enables scientists to look inside matter at the molecular and atomic scale.

Glowing words

The technique is particularly useful for probing the palimpsest because the ink used by the scribe to record Archimedes' work contains iron.

"When the X-rays hit an iron atom it emits a characteristic radiation, it glows," says Dr Bergmann. "When you record the glow you can reconstruct an image of all of the iron in the book."

The glowing words are displayed on a computer screen, giving the researchers the first glimpse of the text in nearly 800 years.

"It's like receiving a fax from the 3rd Century BC," said Mr Noel. "It's the most sensational feeling."

Each page takes 12 hours to reconstruct as the highly focused beam of X-rays, the width of a human hair, sweeps across the page.

The team have until the 7 August this year to scrutinise the palimpsest, before the synchrotron is switched off for maintenance.

During that time they hope to scan between 12 and 14 pages, paying particular attention to the areas covered with the forged paintings.

The public can watch the researchers as they reveal the glowing ancient text during a live webcast at 2300 GMT on 4 August.

A Hercules C-130 transport airplane will take the flightless birds to Pelotas in southern Brazil on Sept. 23 for the first leg of their journey home, the Air Force's press office said. There, they will be examined by veterinarians at the Marine Animal Rehabilitation Center of the Eliezer de Carvalho Rios Oceanographic Museum.

From Pelotas, the penguins will be driven to the coast and placed on Navy ships. They will be taken 40 miles offshore before being released into the southern Atlantic.

"Ocean currents will hopefully carry them back to their natural habitat," Candiotto said. "If everything goes smoothly, the penguins should be back in Antarctica within 10 days after leaving Rio."

Every year between June and August, large numbers of penguins arrive in Rio from the Strait of Magellan, Candiotto said by telephone from Rio.

"They are young, inexperienced animals that, in their search for food, get caught in the ocean currents," she said. The birds arrive near Rio extremely debilitated and having lost about two-thirds of their normal body weight. About half die of hyperthermia, hyperglycemia and exhaustion, she added.

Brazil began penguin airlifts in 2000, returning as many as 100 a year to their natural habitat, said Lauro Barcellos of the Oceanographic Museum.

Dogs being walked were seized from their owners and beaten to death on the spot, the Shanghai Daily newspaper reported. Led by the county police chief, killing teams entered villages at night creating noise to get dogs barking, then beat the animals to death, the reports said.

Owners were offered 63 cents per animal to kill their own dogs before the teams were sent in, they said.

The killings were widely discussed on the Internet, with both legal scholars and animal rights activists criticizing them as crude and cold-blooded. The World Health Organization said more emphasis needed to be placed on rabies prevention.

The official newspaper Legal Daily blasted the killings as an "extraordinarily crude, cold-blooded and lazy way for the government to deal with epidemic disease."

"Wiping out the dogs shows these government officials didn't do their jobs right in protecting people from rabies in the first place," the newspaper, published by the central government's Politics and Law Committee, said in an editorial in its online edition.

In an editorial, the official Xinhua News Agency said the killings wouldn't have been necessary if the local government had been more attentive, but called the slaughter "the only way out of a bad situation."

"If they'd discovered this earlier, they could have vaccinated the dogs and ... controlled the outbreak," the editorial said.

The killings prompted calls for a boycott of Chinese products from the activist group People For the Ethical Treatment of Animals.

"We are urging everyone to actively boycott - not a word we use lightly - anything from China given the bludgeoning killing of thousands of dogs," PETA President Ingrid Newkirk said.

She said the group had canceled all orders of merchandise it sells that are made in China. Will Wright, at PETA's European office in London, said the orders were worth about $300,000.

"We believe other groups will join us in expressing outrage over the blatant cruelty to animals the world is witnessing," Wright said.

Mouding County officials defended the slaughter in a region where about 360 of the 200,000 residents suffered dog bites this year, with three people reportedly dying of rabies, including a 4-year-old girl.

"With the aim to keep this horrible disease from people, we decided to kill the dogs," Li Haibo, a spokesman for the county government, was quoted as saying by Xinhua.

Calls to county government offices went unanswered Tuesday. Located in mountains about 1,240 miles southwest of Shanghai, Mouding is famed for its Buddhist shrines.

Unlike in the West, where dogs have long been cherished as companions or helpmates, dogs have rarely had an easy time in China. Dog meat is eaten throughout the country, revered as a tonic in winter and a restorer of virility in men.

Following the communist seizure of power in 1949, dog ownership was condemned as a bourgeois affectation and canines were hunted as pests. Attitudes have softened in recent years, although urban Chinese are still subject to strict rules on the size of their pets and must pay steep registration fees.

About 70 percent of rural households now keep dogs, according to the Chinese Center of Disease Control and Prevention, and increased rates of dog ownership have been tied to a surge in the number of rabies cases in recent years. It said there were 2,651 reported deaths from the disease in 2004, the last year for which data was available.

Access to rabies treatment is also highly limited, especially in the countryside, said Dr. Francette Dusan, a World Health Organization expert.

Effective rabies control requires coordinated efforts between human health, animal health and municipal agencies and authorities, Dusan said.

"This has not been pursued adequately to date in China, with most control efforts consisting of purely reactive dog culls," she said.

Aspens send out suckers to create "clone" trees. But in many stands in the West, including southeastern Idaho, that process is not working. The group wants to figure out why.

The group is made up of workers with the Idaho Department of Fish and Game, Idaho Department of Lands, Idaho Department of Agriculture, U.S. Bureau of Land Management, U.S. Forest Service, ecologists and concerned citizens.

"Right now, they're still building their mailing list," said Wendy Lowe, a consultant hired to run the meetings. "They have chosen to define their membership as anyone interested in participating. They're just getting started. The first thing they wanted to do is learn a lot more about it."

According to Fish and Game, aspen numbers in eastern Idaho have declined 65 percent in the past century. Records show that 45 percent of the Caribou-Targhee National Forest in southeastern Idaho was once covered by aspens. Aspens now cover about 27 percent of the forest.

To try to help aspens, Fish and Game has killed conifers that compete with them for space, said Jennifer Jackson, a regional conservation educator with the agency. The Forest Service also has projects planned to help aspens return.

"The fire cycle has been interrupted," Jackson said. "Conifers have been encroaching on the aspen stands. Aspen communities are so important to wildlife species."

Bartos said that aspen stands tend to burn every 30 to 50 years, a process that causes new clone trees to grow. But Bartos said fire suppression has interfered with that process.

He said planting aspens is difficult in the wild. A better way to bring back aspens, he said, was to help existing populations by giving them additional space.