Fun Facts

A HISTORY OF THE ATLAS

In the mid-1500s, Italian mapmakers began compiling maps of various sizes and binding them together. Today these works are called "IATO" ("Italian, assembled to order") or Lafréri atlases (after Antonio Lafréri, a leading publisher), but the term "atlas" was not applied to them at that time. The first modern-style atlas appeared in 1570, when Flemish cartographer Abraham Ortelius published Theatrum orbis terrarum, containing 53 maps reduced to a uniform size. This was also the first world atlas since Ptolemy's Geographia 1,400 years earlier. In the last decades of the 16th century, Gerardus Mercator became the first to use the word "atlas" in its modern sense with the publication of his Atlas, Sive Cosmographicae Meditationes De Fabrica Mundi. Mercator also began the common practice of picturing the mythical Titan Atlas on the frontispiece of bound map collections.

MAPS AND THE FOUR-COLOR PROBLEM

In creating maps, cartographers came across a practical dilemma: how many colors did one need to ensure that no adjacent region sharing a boundary line was colored the same? In 1852, mathematician Francis Guthrie noticed that he was able to color all the counties in England using only four hues. He wondered if the same were possible for any map, and the hunt to solve the four-color theorem began. Alfred Kempe submitted a widely accepted proof in 1879 and Peter Guthrie Tait posited another one a year later; both proofs stood unchallenged for 11 years until shown to be incorrect. However, in the process of exposing the flaw in Kempe's proof, British mathematician Percy Heawood also demonstrated the validity of the five-color theorem in 1890. Several more four-color proofs were attempted in the twentieth century, but all failed in their ultimate goal. Finally, Kenneth Appel and Wolfgang Haken established the initial theorem in 1976 with the aid of a computer–the first time an important theorem had been solved with considerable computer assistance.