CHAPTER XIV.--Difficulties of the advance--The Pedregal--San
Antonio--Hacienda--Relative position of American and Mexican armies--Path over the Pedregal to Contreras--Valencia disconcerts Santa Anna's plan of battle--American advance and victory at Contreras--San Antonio turned by Worth--Battle of Churubusco--Battle at the Convent and Tete de Pont--Their capture, 391