March 23, after making fifteen miles across a clear, dry prairie, the army came to a road that led to Matamoros, about eighteen miles away on the right, and to Point Isabel, distant nine or ten on the other side; and Taylor, ordering Worth and the infantry to camp and watch for the enemy at a suitable place in the former direction, proceeded to the coast with his cavalry. There he found the transports in sight and the wind favorable. Defences were planned at once; and on the 27th, leaving an engineer, supported by a guard under Munroe, to superintend the construction of them, the General returned to the army, then some ten miles from Matamoros. The next morning all advanced, and soon came to rough defiles. On each side bristled what a soldier described as an irregular, impenetrable mass of "scraggly, scrubby, crooked, infernally illegitimate and sin-begotten bushy trees loaded with millions of thornpins"--that is to say, _chaparral_. Passing this and a few cabins in the midst of corn, cotton and pomegranates, the troops found themselves at the end of their march, Río Bravo, the "Bold river of the North," brown with mud, rolled swift and boiling at their feet; and in plain view about half a mile distant--black with crowded house-tops, gay with flags, and noisy with bugles and barking dogs--lay Matamoros. A rude pole was soon raised; to the music of our national airs the colors went up; and a small masked battery of field guns was planted near them.[7.21] A singular political game then took place between Taylor and Mejía. The former did everything possible to convince the Mexican general that his movement was entirely pacific, and offered to "enter into any arrangements to secure the peace and harmony of the frontier" during negotiations between the two governments; but the latter insisted over and over again that a state of war had been created by the American advance. In spite of this Taylor reminded his officers of the "essentially pacific" and "conciliatory" intentions of the army; yet at the same time he reported the Mexican attitude as distinctly hostile, asked for reinforcements, mounted four 18-pounders to command the city, and about April 7 began what came to be known as Fort Brown, a large, bastioned "field-work" opposite the lower end of the city.[7.22] [THE MEXICAN ATTITUDE]