THE CITY OF MEXICO AND ENVIRONS.
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was then mostly covered by lagoons. An oracle bad commanded them not to found a city till they had come to a spot were an eagle would be seen standing on a rock. Upon exploring the shores of the lagoon, the Aztec rovers beheld the long-sought eagle resting on a cactus, which
grew out of a crevice in the solid rock. Accordingly, they called their city Tenochtitlan, which signifies a "cactus upon a rock."
The device of an eagle, with a serpent in its beak, standing on a cactus that grows out of a rock, has become the escutcheon of Mexico. It is found on the national flag, as well as on the gold and silver coins.
The present capital lies in latitude 19° 25' 45" north, and longitude 99° 5' 15" west of Greenwich. It is built on