Having by burning the Vermilion bridge gained a day's rest for his tired soldiers, Taylor resumed the retreat at noon on the 17th of April, and passing through Opelousas and Washington on the 18th and 19th, on the following day found himself with all his trains behind the Cocodrie and the Boeuf. On the 20th he sent Mouton, with all the cavalry except Waller's battalion, westward over the prairie toward Niblett's Bluff, on the Sabine. Then, with Waller and the frayed remnant of the infantry, day by day wearing away at the edges, Taylor continued his retreat toward Alexandria, halting with what may be called his main body at Lecompte. To hinder the pursuit he burned the bridges over the Bayou Cocodrie and the Bayou Boeuf. Opelousas, miles away from every thing, in the heart of a vast prairie, presented in itself no object for an invading army. Even the temptation of a good position was wanting. Banks meant merely to halt there a day or two for rest, and then, if it should be found practicable to obtain the necessary supplies, to push on rapidly to Alexandria, and dispose for the season of Taylor's disordered fragments. Whether this could have been done will never be known, for although the army had now far outmarched its supplies, and even from its secondary base at Brashear was separated by nearly a hundred miles, and although the campaign had so far been made upon less than half the regular rations for men and animals, supplemented from farm, sugar-house, and prairie, the country on the line of march was no longer to be counted on for any thing save sugar in plenty and a little corn; nevertheless, it might have been possible, by great exertions, to replenish the trains and depots, as well as to fill up the haversacks. Moreover, a three days' march would find the army on the banks of Red River, with a new and ample source of supply open to them, and within easy reach of Grant, provided only the navy might be counted upon to control the waters of that stream and its larger tributaries. Of this Banks had no doubt whatever. To open communication with Grant and to dispose of Taylor had been the chief ends that Banks had proposed to himself in setting out on the campaign. These ends he now held almost in his hand. But on the 21st of April an event occurred that, slight as was its apparent importance, was destined, in the train of consequences, vitally to affect the operations of the Army of the Gulf. This was the arrival at headquarters of Lieutenant Joseph T. Tenney, one of Dudley's aides-de-camp, who had been sent by Augur to find Banks, wherever he might be. With him Tenney brought important despatches from Grant and Farragut. What the contents were and what came of them will be related in the next chapter.