THE AZTECS 189 
cated to Huitzilopochtli and the other to ‘Tlaloc. 
Each temple contained an image of the god to which 
it was dedicated and a sacrificial altar. The walls were 
encrusted with blood of human victims whose hearts 
still beating had been torn out for divine food and whose 
bodies had been rolled down the steep flight of temple 
stairs. The foundations for the great pyramids were 
laid in 1447 by Moctezuma I, the pyramids were com- 
pleted in 1485 while Tizoc was war chief and the final 
dedication ceremonies were held in 1487. 
Several very interesting large sculptures and many 
minor objects have been unearthed on the site of 
Tecpan. In 1790 and 1791 were found three famous 
monoliths, the Calendar Stone, the Stone of Tizoc 
(Sacrificial Stone), and the Statue of Coatlicue. 
Since 1897 many fine pieces of pottery and several 
sculptures have been excavated near the Cathedral 
and placed in the Museo Nacional. 
The Calendar Stone. Thegreat sculptured monu- 
ment known as the Calendar Stone or Stone of the Sun, 
is the most valuable object that has come down intact 
from the time of the Aztecs. It is a single piece of 
porphyry, irregular except for the sculptured face. It 
now weighs over twenty tons and it is estimated that 
the original weight was over twice as much. The 
sculptured disk is about twelve feet in diameter. This 
great stone was transported by men over many miles 
of marshy lake bottom before it could be placed in 
position in front of the Temple of the Sun in the temple 
enclosure that has just been described. It is believed 
to have been set up horizontally and to have served as 
a sort of altar upon which human victims were sacri- 
ficed. The stone was doubtless thrown down from its 
