Rather more than half a mile west of Chapultepec and still farther north of Tacubaya stood a complicated range of low stone buildings known as El Molino del Rey (The King's Mill). They extended in a rambling fashion approximately north and south more than 300 yards, and consisted essentially of a flour mill and a foundry for bronze cannon. The heavy walls and the parapets of the flat roofs, reinforced with sand-bags, made these buildings almost a fort. Nearly half a mile from them toward the northwest lay a very solid stone edifice, at one time a powder magazine, called the Casa Mata, protected now with a small, dry fosse and light, incomplete breastworks. Along the west front of El Molino extended a somewhat irregular drainage ditch, or series of ditches, at this critical time free from water, which then made a bend, passed some twenty-five yards from the south face of Casa Mata, continued in the same direction nearly one fourth of a mile, and finally joined a deep, wide ravine, that ran for a long way northeast and southwest, and could not easily be crossed except (at X) near this junction. For military uses the ditch gained strength from dirt thrown up in front of it and a line of maguey growing some thirty yards back. From it an easy slope, clear of trees but somewhat obstructed with cornfields near the bend, rose toward the southwest for about 600 yards and culminated in a ridge, which overlooked Tacubaya; while west of the ravine and a mile or so from Casa Mata stood the hacienda buildings of Los Morales.[28.1] [Illustration: BATTLES OF MEXICO] [SCOTT'S PREPARATIONS] Inferring from supposed signs of American activity, and also from Scott's peremptory letter, that on the afternoon of September 7 a determined effort would be made to seize Chapultepec and attack the defences of the city, which had not become very strong in this quarter, Santa Anna made special efforts during the sixth to place his most serviceable troops on the terrain just described; and the next day, taking command there in person, he posted and instructed them with particular care. León's and Rangel's brigades were stationed in El Molino; the best of Pérez's brigade garrisoned the Casa Mata; Ramírez's occupied the intermediate space; four guns were placed a little in front of the bend; 3000 or 4000 horse under Alvarez--the first division commanded by him and the second by Manuel Andrade--proceeded to Los Morales; reserves of infantry and artillery lay in the rear, and the cannon of Chapultepec were made ready to sweep the ridge and slope.[28.2]