Washington ? The earliest map using “America” to label part of the New World is going on display in America for the first time.

The 496-year-old Waldseemueller map, sometimes called America’s birth certificate, will be on public view at the Library of Congress starting today.

The library recently completed the $10 million purchase of the 12-panel map covering 36 square feet, the most expensive single item it has ever acquired. It was owned by Prince Johannes Waldburg-Wolfegg, at whose castle in southwestern Germany the document was discovered a century ago. It is the only one known to survive of the 1,000 copies of the map said to have been printed.

“It was a bargain,” said John K. Hebert, chief of the library’s Geography and Map Division. He hopes for important new research now that the map is in the United States.

“AMERICA,” in capital letters, appears on a part showing what is now Brazil.

An inset includes both North and South America, and a drawing of “Amerigi Vespucci.” In an accompanying pamphlet, which will be displayed later, cartographer Martin Waldseemueller wrote that since Vespucci was the first to call it a continent, the land mass should be named after him.

Vespucci, an Italian who came to the New World soon after Columbus, sailed along South America’s north and east coast.

Hebert speculates that Vespucci, or someone not yet identified, may have seen the west coast, too, but he knows of no record of that. At three points, he said, the map gives a surprisingly exact width of South America — a width of 30 degrees of longitude at the equator, for example.

“It’s much more accurate than anyone could guess from just an exploration of the east coast,” Hebert said. He knows of no European exploration on the Pacific coast before the date of the map, 1507.

A full-size facsimile of Martin Waldseemueller's 1507 world map is shown at the Library of Congress in Washington. Americans can get a first look today at the document that gave the name America to the continent 496 years ago: the Waldseemueller map. The Library of Congress recently completed the purchase from Prince Johannes Waldburg-Wolfegg, at whose castle in southwestern Germany the map was discovered a century ago. The map, divided into 12 panels covering a total of 36 square feet, is the only known copy of the 1,000 editions that were printed.

The Waldseemueller map is part of a larger exhibit at the library called “Rivers, Edens, Empires: Lewis & Clark and the Revealing of America.”

President Jefferson and Capt. Meriwether Lewis planned for exploration of the Louisiana Territory even before Jefferson bought it from Napoleon in 1803, doubling the size of the United States. They recruited Lt. William Clark to help lead a band of 40 soldiers and civilians to explore and map the territory.

Like Columbus, Jefferson was looking for an all-water route from the Atlantic to the Far East.

“I was on a trip recently and saw four of the Great Lakes in one day,” Hebert said. “They’re like oceans, so it seemed reasonable to think that there must be some other body of water there that would lead to the Pacific.”

Like Vespucci, Lewis and Clark gave evidence that there was no easy water route to China.

“Jefferson thought the Rockies were a single ridge, like the Appalachians in Virginia,” Hebert said. “When Lewis and Clark looked beyond the first one in the Rockies and wondered how many more there were, it was the end of that dream.”

The exhibit traces the explorations that charted the West. It ends with a map from just before the Civil War that outlined the whole of the United States between the Pacific and the Mississippi.