A sudden and heavy cannonade had already opened from the French Heights--a sure prelude to the attack which was about to take place--and the 69th Regiment was in the act of forming Square, when the Prince of ORANGE rode up to it and asked what it was doing. Colonel MORICE explained that he was forming Square in pursuance of the instructions he had received; upon which His Royal Highness, remarking that he did not think there was any chance of the Cavalry coming on, ordered him to reform Column, and to deploy into line. During this last movement a strong body of French _Cuirassiers_, taking advantage of the surrounding high corn, and of the circumstance of the Regiment lying in a hollow, approached unperceived quite close to the spot, and rushing suddenly and impetuously upon a Flank, succeeded in completely rolling up the Regiment, riding along and over the unfortunate men, of whom great numbers were cut down, and in the midst of the confusion thus created, captured and carried off one of the Colours; in defence of which Major LINDSAY, Lieutenant PIGOT, and Volunteer CLARKE, highly distinguished themselves, and were desperately wounded. Some Officers and men took shelter in the Square formed by the 42nd and 44th Regiments; the mounted Officers gained the other side of the road, pursued by about twenty of the Enemy, and escaped by riding through one of the Hanoverian Battalions lining the Namur road. The 30th Regiment, which had also been deployed into line by the Orders of the Prince of ORANGE, most fortunately discovered, in sufficient time, the approach of Cavalry (notwithstanding the extraordinary height of the rye, which greatly impeded all observation), formed Square with remarkable rapidity, and, reserving their fire until the very last moment, they completely dispersed and drove off a body of PIRÉ's Lancers, and a portion of KELLERMANN's _Cuirassiers_, which troops had made a charge upon them, enveloping two faces of their Square. PICTON, who, from the opposite side of the high road, was an eye witness of this scene, was so much pleased with the perfect steadiness of the Regiment, that, seizing a favourable opportunity of galloping up to it, he called for the Commanding Officer, and told Lieutenant Colonel HAMILTON that he should report to the Duke the gallant conduct of his Corps. Indeed the steadiness and gallantry of the 30th in this Battle were so conspicuous as also to draw upon them the well merited commendations of the Prince of ORANGE, and Generals ALTEN, HALKETT, and KIELMANSEGGE. The 73rd Regiment (under Colonel HARRIS), and the Brunswickers, were equally on the alert; but the French Cavalry, on finding them prepared, diverged towards the high road.