Two lines of operation were open to Suchet, the one, short and direct, by the high road leading from Zaragoza through Fraga to Lerida; the other circuitous, over the Sierra de Alcubierre, to Monzon, and from thence to Lerida. The first was inconvenient, because the Spaniards, when they took Fraga, destroyed the bridge over the Cinca. Moreover, the fortress of Mequinenza, the Octogesa of Cæsar, situated at the confluence of the Segre and the Ebro, was close on the right flank, and might seriously incommode the communications with Zaragoza, whereas the second route, although longer, was safer, and less exhausted of forage and provisions. Monzon was already a considerable military establishment, the battering train consisting of forty pieces, with seven hundred rounds of ammunition attached to each, was directed there, and placed under the guard of Habert’s division, which occupied the line of the Cinca. Leval leaving general Chlopiski with a brigade at Daroca, to observe Villa Campa, drew nearer to Zaragoza with the rest of his division. Musnier marched with one brigade to Alcanitz, and was there joined by his second brigade, which had been conducted to that point, from Terruel, across the Sierra de Gudar. And while these movements were executing, the castles of Barbastro, Huesca, Ayerbe, Zuera, Pina, Bujarola, and other points on the left of the Ebro, were occupied by detachments. The right bank of that river, being guarded by Leval’s division, and the country on the left bank, secured by a number of fortified posts, there remained two divisions of infantry, and about nine hundred cavalry, disposable for the operations against Lerida. On the Spanish side, Campo Verde was with O’Donnel at Manreza, and Garcia Novaro at Taragona, having small detachments on the right bank of the Ebro to cover Tortoza; Perenna with five battalions occupied Balaguer on the Upper Segre. Such were the relative situations of both parties, when general Musnier quitting Alcanitz towards the end of March, crossed the Guadalupe, drove Novarro’s detachments within the walls of Tortoza, and then remounting the Ebro, seized some boats, and passing that river at Mora and at Flix, communicated as I have before related, with colonel Villatte of the seventh corps. And while this was passing on the Ebro, general Habert crossed the Cinca in two columns, one of which moved straight upon Balaguer, while the other passed the Segre at Camarasa. Perenna, fearing to be attacked on both sides of that river, and not wishing to defend Balaguer, retired down the left bank, and using the Lerida bridge, remounted the right bank to Corbins, where he took post behind the Noguerra, at its confluence with the Segre.