Our march was now hastened, and in less than an hour we debouched from the narrow gorge into the open plain before the town of Castlebar. A few shots in our front told us that the advanced picket had fallen in with the enemy, but a French cheer also proclaimed that the Royalists had fallen back, and our march continued unmolested. The road, which was wide and level here, traversed a flat country, without hedge-row or cover, so that we were able to advance in close column, without any precaution for our flanks; but before us there was a considerable ascent, which shut out all view of the track beyond it. Up this our advanced guard was toiling, somewhat wearied with a seven hours' march and the heat of a warm morning, when scarcely had the leading files topped the ridge, than, plump went a round shot over their heads, which, after describing a fine curve, plunged into the soft surface of a newly plowed field. The troops were instantly retired behind the crest of the hill, and an orderly dispatched to inform the General that we were in face of the enemy. He had already seen the shot and marked its direction. The main body was accordingly halted, and, defiling from the centre, the troops extended on either side into the fields. While this movement was being effected Humbert rode forward, and crossing the ridge, reconnoitred the enemy. It was, as he afterward observed, a stronger force than he had anticipated, consisting of between three and four thousand bayonets, with four squadrons of horse, and two batteries of eight guns, the whole admirably posted on a range of heights, in front of the town, and completely covering it. The ridge was scarcely eight hundred yards' distance, and so distinctly was every object seen, that Humbert and his two aids-de-camp were at once marked and fired at, even in the few minutes during which the "reconnoissance" lasted. As the General retired the firing ceased, and now all our arrangements were made without molestation of any kind. They were, indeed, of the simplest and speediest. Two companies of our grenadiers were marched to the front, and in advance of them about twenty paces were posted a body of Irish in French uniforms. This place being assigned them, it was said, as a mark of honor, but in reality for no other purpose than to draw on them the Royalist artillery, and thus screen the grenadiers. Under cover of this force came two light six-pounder guns, loaded with grape, and intended to be discharged at point-blank distance. The infantry brought up the rear in three compact columns, ready to deploy into line at a moment.