“That’s a staggering number,” I said. “Maybe enough to turn Tina Barr into a thief.”

“I don’t know why she wouldn’t have been tempted by it,” Jill Gibson said. “Half the members of my board would sell their souls to own this map.”

“If you’re looking for the Holy Grail of rare maps,” the petite librarian said to us, grinning as she gazed at the woodcut that Mike had placed on the table in front of her, “this is as good as it gets.”

Bea Dutton was in charge of the map division of the library, home to more than half a million of them and more than twenty thousand atlases and books about cartography. Jill had called her to come in to the office early, moments after Mike made his find, and she appeared within the hour.

“Did you know this map was missing?” Mike asked.

“What do you mean?” Bea said. Her white cotton gloves-a tool of her trade-looked more civilized than Mike’s plastic ones. She was short and slight, and leaned her elbows on the long trestle table to get a good look at her subject.

“I’m sure you must know exactly when something as precious as this disappeared from your collection.”

“You’ve made a bad assumption, Detective. We’ve never had a map like this under our roof. I can’t even imagine what this portion of it was doing here. I’ve been waiting a professional lifetime to see if another one of these treasures came to market. The only known original in the world is in the Library of Congress. Didn’t Jill tell you?”

“This is your bailiwick, Bea,” Jill said. “I’ve seen it on your wish list but really didn’t know whether or not we owned any of the individual panels.”

“Let me explain what you’ve found here,” Bea said, inviting Mercer, Mike, and me to sit around the table. We were on the first floor of the library, in an elegant room with dark wood paneling, three long tables, and copies of antiquarian maps of all varieties mounted in gilded frames along its walls. Only the coat of arms of the City of New York on each pedestal of the tables betrayed that we weren’t being entertained in a fancy British manor home. “That is, if I can take my eyes off it. You’re looking at one of the pieces of what many people call America ’s birth certificate.”

Mercer looked closely at the ancient drawing. “How so?”

“This panel is part of a map that was the very first document in the world on which the word ‘ America ’ appears as the name for a body of land in the Western Hemisphere.”

Mike bent forward to look for the notation.

“Not on this particular fragment, Mike. Remember, there are twelve pieces of this beauty, each the same size as this. Once joined together, the map is four feet tall by eight feet wide. It’s quite an unusual masterpiece.”

“Who created it?” I asked. “What made it so special?”

“The primary author was Martin Waldseemüller, a German cleric and cartographer who spent his life in Saint-Dié, France, part of a small intellectual circle there. Until this was published in 1507, the European body of knowledge about the world’s geography was entirely based on the second-century work of Ptolemy. This map,” Bea said, tapping her gloved finger on the table, “radically changed the worldview.”

“In what way?” Mike asked.

“Think of it, Detective. The Spanish and Portuguese kept returning to Europe at the end of the fifteenth century with dramatic news of explorations down the African coast and across the Atlantic, where no Europeans had ever been before. To us, this map looks incredibly accurate, but to his contemporaries, Martin’s map ignited a great deal of debate. It presented a revolutionary vision of the world.”

“Why?”

“This was the first document ever created that depicted a Western Hemisphere, standing alone between two oceans, the first to represent the Pacific as a separate body of water, and the first to give the new world its own name: ‘America.’ In those times, they were completely radical ideas.”

Mercer’s huge frame was bent over the table as he examined the fine print in the woodcut. “Used to be, according to Ptolemy, the Atlantic stretched from Europe and Asia right over to Japan, Cathay, and India, with a little bit of terra incognita along the way.”

“Exactly,” Bea said.

“What about Columbus?” Mike asked. “He was over here before Vespucci. How come he didn’t get the whole caboodle named for Christoforo instead of Amerigo?”

“Well, that’s another reason this map was so controversial. Both men made several voyages across the Atlantic. Vespucci enjoyed more popularity throughout Europe because he wrote many publications that were read widely by intellectuals and explorers-he was a best seller in his day-and he actually went farther down the coastline of South America, convinced there was another ocean, entirely separate, on the western side of that landmass,” Bea said. “ Columbus, on the other hand, died in disgrace. Do you remember your history?”

“Yeah, I guess he did the first Terra Nova perp walk, didn’t he?” Mike said. “He was the governor of Hispaniola, and the king had him arrested for mismanagement.”

“Right. He also maintained, till his dying day, that he had reached Asia on one of his voyages. It was Vespucci who realized that both he and Columbus had come upon another continent-not Asia, not the Indies -that most Europeans didn’t know existed. So he got the credit,” Bea said. “It’s kind of remarkable when you think that this single obscure mapmaker-as great as he was-chose the name for the entire Western Hemisphere.”

“And that he named it for a man who was still alive at the time, Amerigo Vespucci. No waiting for the verdict of history or going the traditional route of naming it for a mythological figure,” Mercer said, straightening up.

“Then he feminized it,” Bea said. “Don’t forget that, Alex. Asia and Europa got their names from mythical women-so that tradition of the feminine ending of a continent remained intact.”

“But it’s this little group of clerics and geographers who were so taken by Vespucci’s writings that they placed his name on this map?” I asked.

“No longer Terra Incognita or Terra Nova, as the new world was called by the ancients. Martin and his team just went ahead and christened these lands America -their very own idea,” Bea said, “and as soon as this work was published, cartographers everywhere adopted that name for the Western Hemisphere.”

“How many of these maps were printed at the time?” Mercer asked.

“A very sizable run for those days, actually. One thousand copies.”

“What became of them all, do you think?”

Bea smoothed her curly red hair with the back of her glove. “Like many objects of intellectual interest in the sixteenth century, part of the plan was to distribute them as widely as possible across Europe, to spread the new knowledge that the explorers were acquiring with each trip they made. That broad dissemination accounts for the loss of many things, and makes the ones that made it through time, warfare, pillaging, and the usual historical turmoil so very rare.”

“And its size?” I asked.

“Another problem indeed. The larger an old map, the rarer it has usually become. The huge size and very inconvenience of form of this one certainly quickened its destruction. It was so much greater than many of the charts of the day, folded once-never bound-inside an elephant folio. So the mere difficulty of keeping twelve large panels like this one in pristine condition, and not allowing the dozen sections of it to be separated, was an enormous obstacle to its survival.”

“What’s an elephant folio?” Mike asked.

“It’s the term for a very large book, Detective. Usually greater than two feet tall. That Audubon in which you found the map is actually a double elephant folio-easy to conceal your map in because it’s so large. Let me show you something.”