CHAPTER XIII. 1847.

Along the Chalco route there were no more fortifications, but west of lakes Chalco and Xochimilco, a line of entrenchments had been commenced, connecting the fortified hacienda, or massive stone plantation house of San Antonio, about six miles south of the city, with the town of Mexicalzingo. West of this hacienda, the Pedregal, a vast, broken field of lava, spread out along the edge of the main road, and skirting it to San Agustin, extended high upon the mountain slopes still further west near San Angel and Contreras, whose neighboring fields were cut into deep ravines and barrancas by the wash from the declivities. The Pedregal was a most formidable obstacle in the march or manœuvres of an army. But few levels of arable land were found among its rocky wastes. It admitted the passage of troops at but few points, and was entirely impracticable for cavalry or artillery, except by a single mule-path.² North of San Angel and the edge of the Pedregal, at the distance of about four miles, rose the solitary hill and castle of Chapultepec, which had been amply prepared for defence; and still further north on the same line, frowned the stern ridges of the sierra, cut by barrancas and profound dells, until the ring of the outer series of military works was thus finally united at the pass beyond Tenepantla. But inside of this formidable barrier of outworks, nearer the city, another line of fortifications had been prepared to dispute the American march. The first, and perhaps the most important of these, was at Churubusco, a scattered village lying midway between San Agustin and the city of Mexico, directly on the road, at a spot where the stream or rivulet of Churubusco runs eastwardly from a point on the road from San Angel to the capital, towards the lake of Xochimilco. The sides of the water course were planted