From Fray Bernardino de Sahagún, Florentine Codex, Book 12, Chapter 31 (Mexica)

Here it is told how the Spaniards came with the brigantines, pursuing those who were in boats.

And when they had prepared the cannons, they fired at the wall. The wall cracked and broke open. And the second time it was hit, the wall fell to the ground, destroyed; it burst open, perforated, [there were] holes in it. Then, like the other time, the road was completely cleared [of warriors]. And the warriors who were by the wall dispersed. All fled from there, all were with fear. And all of the different [supporters of the Spaniards] advanced filling each canal. They quickly leveled them with stones, adobes, and even with some logs to impede the flow of water.

And after the canals had been filled, some [men on] horses came, perhaps ten of them; they rode in circles, spinning, turning, twisting. [And more men on] horses came, following the others. And some of the Tlatelolcas, who had quickly entered the palace which had been the home of Moctezuma, then emerged in terror to confront the horse[men]. [The Spaniards] lanced a Tlatilulcan, but when they had lanced him, he was able to take hold of [the Spaniards'] iron lance. Then his companions took [the lance] from [the Spaniards'] hands, throwing him on his back [and off of the horse]. When he fell to the ground, they struck him repeatedly, they struck him on the back of the head. He died there.

Then the Spaniards sent everyone, they all moved together; they reached Quauhquiahuac [the Eagle Gate]. And they took with them the big cannons and placed them at Quauhquiahuac. (The reason it is called Eagle Gate is that an eagle stood there, carved in stone. It was very big, very high and very stout, and enclosing it were an ocelot standing on one side, and on the other side [was] a wolf, also carved in stone). And when . . . [they saw the cannons], the great warriors in vain took refuge behind the stone columns; there were two rows of them, eight altogether. And the roof of the Coacalli was also full of warriors. None of them would come out into the open.

And [at first] the Spaniards did nothing; when they fired the cannon, it grew very dark, and smoke spread. Those who had been hiding behind the columns fled; and all of those on the roof jumped down and ran far away. The [the Spaniards] brought the cannon up and placed it on the large, round stone (of gladiatorial sacrifice). On top of the temple of Huitzilopochtli, [priests] in vain were holding vigil. [Then the priests] beat their atabales [drums]; with all force, they beat their drums. Then two Spaniards climbed up [to the roof of the temple]. There they clubbed [the drummers]; and after they beat them, they tossed them down; they threw them down.

And the great captains and the warriors, who had been fighting in boats, came onto dry land, and those who rowed the boats were youths, [only they] continued to guide the boats. And at this point, the warriors inspected the streets, with much running and shouting, saying "Oh warriors, come, arise . . . !"

And when the Spaniards saw [that the Mexicas] were coming and were [poised] to pursue them, they regrouped and gripped their swords. [Then] there was a rush, general confusion. From one side to another, arrows fell on them; and from both sides, they were pelted with stones. [Both sides had to retreat] [The Mexicas] withdrew to Xoloco to catch their breath, to recover.

The Spaniards also retreated to their camp in Acachinanco. But they abandoned the cannon they had placed on the stone of gladiatorial sacrifice. Then the Mexica warriors captured it, dragged it forward, tossed it in the water. They tossed it in the water at Tetamazolco, el Sapo de Piedra.