nearer the centre, and the great Plaza upon which stands the Cathedral, in the south-east corner. The houses are built of stone, in the old Spanish style, with flat roofs, and battlements, or parapets, between two and three feet high; and, with the exception of the public edifices around the main plaza, they are generally but one story in height. To almost every house there is attached a small garden inclosed by stone walls. The streets are laid out with great regularity, running parallel to each other, with the intersecting streets crossing at right angles.
The natural position of the city rendered it easy of defence, and every advantage had been improved to the utmost. On the north side of the town, between the road to Monclova and that to Marin, there was a large rectangular fortress, known as the citadel, covering nearly three acres of ground, with four bastion fronts, surrounded by a work of solid masonry, and supplied with heavy guns. At the north-eastern angle, in the suburbs, there was a strong redoubt of masonry of four faces, with an open gorge of ten feet, prepared for four guns, overlooked and commanded by a large stone house in the rear, also fortified. South of this was a second redoubt of four faces, with three guns, and defended by an open gorge of twenty feet, commanded by another redoubt with three guns, overlooking the Caiderita road crossing the Arroyo San Juan by the bridge Purissima, which was also defended by a tête du pont of masonry. And still further south, there were two other redoubts, only one of which, with three guns, was occupied, having in its rear a stone house prepared for infantry, with loop-holes and sand-bags. All these redoubts were connected by fleches of masonry, or breastworks of earth and brush. Along the southern
