The Aztecs - Part 2 - Knowledge
We
get a lot of information on the Aztecs from the books they wrote called
Codexes. A codex was written on long strips of fig tree bark paper, 15cm
by 12m long and folded pamphlet style. From Codexes like the Tro-Cortesianus
we learn about Aztec life and beliefs. The Aztec universe consisted of
Tenochtitlan surrounded by Texcoco lake, with the 13 layers of heaven
above the earth, the the 9 layers of the underworld beneath the earth.
They practiced astrology and astronomy. To the right is a copy of a drawing
in one of the codexes, showing how Aztec priests would use a pair of crossed
sticks to make sure they were looking at the sky from the same points.
They could predict eclipses, chart the movement of celestial bodies and
named the constellations they saw. They figured out the length of a year
on Venus.
The Aztecs used a vigesimal counting system based on the unit of 20 and
had 2 calendars - a solar calendar and a sacred almanac known as the tonalpohualli.
The solar calendar 365 days long plus a few more hours. Divided into 18
months with 20 days each, each year had 5 extra days which were considered
unlucky. 52 years formed one Aztec century. Priest kept track of the passing
of years by saving a symbolic reed every year. At the end of a 52 year
period, the bundle of reeds was burnt at a "binding of the years"
ceremony. At such ceremonies, all fires were put out and all idols and
household utensils discarded. Stone carvings were made of such bundles
with a date glyph carved on it and represented the death of a century.
Throughout the years, the tonalpouque, or divining priests, used the tonalpohualli
to predict religious events which were recorded in sacred books called
tonalamatl (paper or book of the days).