The mystery would not be easily cracked, given that the compound is 40 times bigger than New York City's Central Park.
In August 2005 Salinas drove south and set up his Geo-Radar.
Within hours of arrival, Salinas had immediately found the buried objectsin this case rocket launchers, grenades, and detonators.
"The police announced the discovery the next day," Salinas says proudly.
In September 2005 Salinas announced that he had found gold and buried treasure on the Juan Fernÿndez Islandsalso known as the Robinson Crusoe islandsoff the coast of Chile (see Chile map).
When Chilean authorities claimed the reported treasure as government property, a standoff developed.
Wagner Technologiesthe local company that financed Geo-Radar's developmentsaid it would donate 60 percent of any treasure to Chilean charities.
Even so, the government refused to renounce its claim, and the supposed treasure remains in dispute and unexcavated.
Put to the Test
Recently, Salinas asked a Chilean university to study the machine and put the questions surrounding it to rest.
"We were tired of everyone questioning that the machine worked," Salinas said.
In early May the results came in, and the Geo-Radar jumped back into local headlines.
University investigators announced laboratory and field tests indicating that the Geo-Radar technology is capable of quickly finding copper deposits, petroleum, and gold bullion at depths of up to 600 feet (283 meters).
"This reduces the time of exploration from three months to one day," said engineering professor Ricardo Neira Navarro at a press conference in Santiago, the national capital.
Neira, of Chile's Universidad Tecnológico Metropolitano (UTEM), told reporters that Geo-Radar was 98 percent effective in finding and mapping underground copper deposits as deep as 600 feet (183 meters).
"This is a revolutionary tool for finding minerals, petroleum, or water," he said. "You rapidly can focus on the place to exploit."
Built to Find Mines
"I built this machine to find buried antipersonnel mines," explained Salinas as he showed pictures of early prototypes of the machine, which had legs like a spider's.
To prevent the prototype from detonating land mines, Salinas designed each "foot" to weigh no more than 5 ounces (140 grams).
Chile's northern borders with Bolivia and Peru are littered with thousands of mines. Few maps of the mines exist, and Salinas began his robot research 12 years ago with the goal of winning contracts to find, deactivate, and remove the explosives.
When he finished building the machine in 2004 and ran field tests, Salinas says, the machine surprised him with its abilities to find water, petroleum, and buried metals. Salinas refuses to patent the machine, saying the technology is "an industrial secret."
He will say only that the machine searches for materials based on their atomic composition.
"I program the machine with 1,500 different [atomic] profiles. The machine sends out a signal," Salinas explained.
"When that signal finds one of the searched-for elements, it bounces back. Then I have an algorithm [computer procedure] which analyzes the elements that have been detected."
Not everyone has been smitten with Salinas or his robot.
Leopoldo Soto, President of the Chilean Physics Society has been dubious of the invention since it first arrived on the scene last September.
"If the apparatus does what they say," Soto told Chilean magazine Ercilla, "it would be truly stunning given that with what we know today of physics, it is not possible in any part of the world.
"In other words, they would have had to discover a new physics."
Mario Favre, a physics professor at Catholic University in Santiago, is outright dismissive.
"What the owners of the machine say is simply delirious," Favre said.
Favre admits that the technology allegedly used by Salinasbouncing a nuclear signal off materials to search for specific atomic compositionsworks.
"But to reach beyond 30 centimeters [12 inches] of depth is today considered a technological advance. And here we are talking about 50 meters [164 feet]."
While other physicists and scientists have openly ridiculed Salinas and his invention, Soto, of the Chilean Physics Society, has been more cautious.
At the peak of the Chilean debate over Geo-Radar, he said, "Let's be open-minded and give Salinas the possibility that he has discovered something that he does not know how to explain but that (the robot) does what he says."
Businessperson Juan Costella Montt doesn't care how it works. "At 300 meters (1,000 feet) the machine found the percentage of copper within 2 percent of what we know to be the actual deposits," Costella said.
The businessman runs a 15-million-U.S.-dollar-a-year copper-exploration company in northern Chile and works closely with Codelco, the world's largest copper producer.
Costella oversaw the Geo-Radar tests and compared the results to maps compiled from traditional methods, including drilling out core samples.
"Without a doubt," Costella said, "[Geo-Radar] works."
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