By Mark Mancini, Mental Floss
Geophysicists recently updated the World Magnetic Model—navigational
data used for everything from cell phones to satellites—and found that
magnetic north, a spot once located in Arctic Canada, is moving quickly toward Siberia. But even this discovery doesn't quite explain why maps always feature north at the top.
There’s
nothing inherently upward about north. Some early Egyptian maps put
south on top, while in medieval Europe, Christian cartographers tended
to give that distinction to east, since you had to turn that way to face
Jerusalem. Others placed east on top because of the rising Sun (that’s
why we orient ourselves). And early American settlers sometimes
used maps with west on top, because that was the direction they were
often heading.
If anyone deserves the blame for today’s northward bias, it’s Claudius Ptolemy. In the 2nd century, he wrote the influential Geographia,
which featured a “global” map with north on top. No one’s positive why
he positioned it that way, but it may be that the Library of
Alexandria—where he did his research—simply didn’t have much information
on the Southern Hemisphere. During the Renaissance, Ptolemy’s work was
revived. By then, the phenomenon of magnetic north had been discovered,
making his layout even more appealing to mapmakers.
The magnetic north pole, however, was not located until 1831. On an otherwise disastrous expedition to Arctic, British explorer James Clark Ross
discovered the pole—the spot where a compass needle on a horizontal
axis points straight down—on the west coast of Canada's Boothia
peninsula. "I must leave it to others to imagine the elation of mind
with which we found ourselves now at length arrived at this great object
of our ambition," Ross recalled. "Nothing now remained for us but to return home and be happy for the rest of our days."
