The Earl of UXBRIDGE, on perceiving the advance of the French Cavalry by La Haye Sainte, on the British right of the Charleroi road (the same alluded to as having dispersed the Hanoverian Lüneburg Battalion and BARING's Skirmishers of the Legion), as also the approach of the Infantry Columns which constituted the attack upon the Allied Left Wing on the opposite side of that road, decided upon a simultaneous charge by the Heavy Cavalry Brigades of Lord EDWARD SOMERSET and Sir WILLIAM PONSONBY; the former against the Enemy's Cavalry, the latter against his masses of Infantry. The resolution was scarcely formed when he proceeded to carry it into instant execution. Riding up to Lord EDWARD SOMERSET, he ordered him to prepare to form Line, keeping the Blues in support: and galloping on to PONSONBY's Brigade on the opposite side of the high road, he ordered that Officer to wheel into Line as soon as he saw the other Brigade do so, and to hold the Scots Greys in support. He then returned to the Household Brigade, and immediately put the whole in motion. As this was the first grand attack made by the French on that day in fair open Field, Lord UXBRIDGE felt very desirous, in meeting it, to establish, if possible, the superior prowess of the British Cavalry; and thus to inspire it with confidence, and cause it to be held in respect by its opponents. He, therefore, with a view to excite the courage and heighten the enthusiasm of his followers, led the advance in person, placing himself in front of the Left of SOMERSET's Brigade, so as to be at about the centre of the Line when the Brigades should unite, on the continuation of the advance, in front of the Allied position. Nobly and faithfully did these brave Dragoons fulfil his anxious expectations. For the purpose of ensuring efficient support to his Cavalry attacks, Lord UXBRIDGE had, before the commencement of the Battle, intimated to the Generals of Brigade that as he could not be present everywhere to give Orders, he expected they would always take upon themselves to conform to, and support, offensive movements in their front; and having on this occasion Light Cavalry Brigades on either Flank of the charging force, he felt in a great degree justified in placing himself in Front Line, particularly as he had assigned to each of the advancing Brigades its own immediate Support.