he found occupied by
Cadwallader's and Smith's brigades, and a regiment of Pierce's brigade
under command of Colonel George Washington Morgan. When General
Valencia's advanced forces were driven in by Twiggs's division on the
_pedregal_, Valencia announced (August 19th, 2 P.M.) to
General Santa Anna at San Antonio that the enemy were approaching
Padierna, the artillery had opened fire, and the battle had begun.
General Santa Anna at once, on receipt of this information, sent an
officer to Coyoacan with orders to General Perez to move at once to
Padierna, and himself with two regiments and five pieces of artillery
proceeded to join him. He arrived at Coyoacan just at the time when
the command of Perez was moving, and he ordered it to move rapidly.

On the evening of August 19th General P.F. Smith was in San Geronimo
with three brigades of infantry, but without cavalry or artillery. His
communications with the main army were cut off except through the
_pedregal_. He determined to attack, however, the next morning at
daylight, carry the enemy's works, and establish his communications
with the main army. His disposition of troops was as follows for the
night: Cadwallader's command in the outer edge of the village of San
Geronimo, Riley's brigade parallel to it, the Rifles on the right, and
the Third Infantry in the churchyard. In the night Captain R.E. Lee
arrived, bearing a letter from General Scott asking to be informed of
affairs beyond the _pedregal_. The information sought for was given,
and Captain Lee was requested to inform General Scott of General
Smith's intention to attack Valencia next morning, and asking that a
diversion be made on Valencia's front. General Shields arrived at
midnight, and was left to hold the village and cut off the enemy's
retreat. In the meantime Colonel Ransom abandoned Padierna, which was
soon afterward occupied by General Valencia's forces, but not without
stout resistance by the small detachment left there.

At nightfall General Santa Anna fell back to San Angel, but failed
to give notice of the movement to General Valencia. Mexican
history states that at 9 P.M. Ramero and Del Rio arrived at
Valencia's headquarters and delivered an order from Santa Anna to
Valencia to retire. General Solos, however, who was present, denies
this, saying that the order was qualified by one to spike the guns,
destroy the ammunition, and saving only what could be safely
transported. General Valencia decli