Freire and Eben, with fourteen guns and twenty-five thousand men, were at Braga, in second line, their outposts being on the Cavado, and at the strong passes of Ruivaens and Venda Nova: but of these twenty-five thousand men, only six thousand were armed with muskets; and it is to be observed that the militia and troops of the line differed from the armed peasantry only in name, save that their faulty discipline and mutinous disposition rendered them less active and intelligent as skirmishers, without making them fitter for battle. The bishop, with his disorderly and furious rabble, formed the third line, occupying the entrenchments that covered Oporto. Such was the state of affairs, and such were the dispositions made to resist the duke of Dalmatia; but his army, although galled and wearied by continual toil, and when halting, disturbed and vexed by the multitude of insurrections, was, when in motion, of a power to overthrow and disperse these numerous bands, even as a great ship feeling the wind, breaks through and scatters the gun-boats that have gathered round her in the calm. CHAPTER II. SECOND INVASION OF PORTUGAL. The Entre Minho e Douro and the Tras os Montes lying together, form the northern part of Portugal, the extreme breadth of either, when measured from the frontier to the Douro, does not exceed seventy miles. The river Tamega, running north and south, and discharging itself into the Douro, forms the boundary line between them; but there is, to the west of this river, a succession of rugged mountain ridges, which, under the names of Sierra de Gerez, Sierra de Cabrera, and Sierra de Santa Catalina, form a second barrier, nearly parallel to the Tamega; and across some part of these ridges any invader, coming from the eastward, must pass to arrive at Oporto. Other Sierras, running also in a parallel direction with the Tamega, cut the Tras os Montes in such a manner, that all the considerable rivers flowing north and south tumble into the Douro. But as the western ramifications of the Sierras de Gerez and Cabrera shoot down towards the sea, the rivers of the Entre Douro e Minho discharge their waters into the ocean, and consequently flow at right angles to those of Tras os Montes. Hence it follows, that an enemy penetrating to Oporto, from the north, would have to pass the Lima, the Cavado, and the Ave, to reach Oporto; and, if coming from the east, he invaded the Tras os Montes, all the rivers and intervening ridges of that province must be crossed before the Entre Minho e Douro could be reached.