Although the enemy had doubtless reconnoitred us from the opposite shore, and ascertained our position, he could not form any accurate idea of our numbers, for with a view to deceive him, we kept the men in constant motion, sometimes showing a part of them on the prairie, then causing them to disappear again behind the vines and bushes. This was all very knowing for young soldiers such as we were; but, on the other hand, we had committed a grievous error, and sinned against all established military rules, by not placing a picket on the further side of the river, to warn us of the approach of the enemy, and the direction in which he was coming. There can be little doubt that if we had earlier notice of their approach, thirty or forty good marksmen--and all our people were that--might not only have delayed the advance of the Mexicans, but perhaps even totally disgusted them of their attempt to cross the Salado. The hollow way on the other side of the river, leading to the ford, was narrow and tolerably steep, and the bank was at least six times as high as on our side. Nothing would have been easier than to have stationed a party, so as to pick off the cavalry as they wound through this kind of pass, and emerged two by two upon the shore. Our error, however, did not strike us till it was too late to repair it; so we were fain to console ourselves with the reflection that the Mexicans would be much more likely to attribute our negligence to an excess of confidence in our resources, than to the inexperience in military matters, which was its real cause. We resolved to do our best to merit the good opinion which we thus supposed them to entertain of us. When the whole of the dragoons had crossed the water, they marched on for a short distance in an easterly direction: then, wheeling to the right, proceeded southward, until within some five hundred paces of us, where they halted. In this position, the line of cavalry formed the chord of the arc described by the river, and occupied by us. As soon as they halted, they opened their fire, although the could not see one of us, for we were completely sheltered by the bank. Our Mexican heroes, however, apparently did not think it necessary to be within sight or range of their opponents before firing, for they gave us a rattling volley at a distance which no carbine would carry. This done, others galloped on for about a hundred yards, halted again, loaded, fired another volley, and then giving another gallop, fired again. They continued this sort of _manège_ till they found themselves within two hundred and fifty paces of us, and then appeared inclined to take a little time for reflection.