The Library of Congress has completed the $10 million purchase of the only known copy of the 1507 world map by Martin Waldseemüller from Prince Johannes Waldburg-Wolfegg, thanks to the generosity of the Congress of the United States, Discovery Channel, Gerald Lenfest, David Koch and a number of other donors. The map has been in the custody of the Library of Congress since late June 2001, when the Library made an initial down payment toward its purchase