During these assaults on the centre of the British line, the French cuirassiers had advanced to the charge in the face of a terrific fire from the artillery in front of the British infantry. The infantry awaited it, formed in a double line of squares, placed checkerwise, so that the sides of each square could fire a volley on the advancing cavalry, and protected in front by a battery of thirty field-pieces. The French cuirassiers rode up to the very mouths of the cannon, charged the artillerymen, drove them from their guns, and then rode fiercely on the squares behind. These remained steadfast, withholding their fire until the French were within a few yards of their bayonets, and then opened on them with deadly effect. The cavalry was all but broken, then rallied and renewed their charge. This they did several times, and always with the same result. Sometimes they even rode between the squares, and charged those of the second line. As the cuirassiers retired the artillerymen rushed from behind the squares, formed four deep, manned their guns, and fired grape-shot with terrible effect on the retreating body of gallant but ineffective cavalry.
At length protracted exposure to such a murderous fire completed the ruin of these fearless cavaliers, the far greater part being annihilated in this part of the battle.
When the relics of the cuirassiers at last withdrew, the French cannonade opened up furiously once more all along the line. It was vigorously returned, but the effect was far more devastating amidst the British ranks than in those of their assailants. The English were then commanded by Wellington to lie flat on the ground for some space, in order to diminish its effects. The Duke had by this time lost 10,000 men and Napoleon possibly a few more.
It was now 4 o'clock and about this time the Emperor received intelligence from Gembloux, that, notwithstanding his repeated orders, Marshal Grouchy had not left his encampment at that place till after 10 o'clock in the morning, in consequence, it was said, of the state of the weather. The body of ten thousand men, under Count Lobau and General Daumont, were now in action with the Prussians under Bulow, near St. Lambeth. The cannonade continued for considerable time; the Prussian centre was then attacked and beaten back, but its wings advancing, Count Lobau was obliged to retire.
At this crisis Napoleon dispatched General Dufresne, with two brigades of infantry of the young guard, and twenty-four pieces of cannon, and the Prussian advance was checked. They still endeavored to out-flank the French right, when several battalions of the Old Guard, with sixteen pieces of cannon, were sent forward; the Prussian line was then out-flanked, and Bulow driven back.
At about 5 o'clock Count d'Erlon had taken possession of the village of Ter-la-Haye; out-flanking the English left and Bulow's right. It appears that Count Milhaud's cuirassiers—which Ney had so often led against the enemy, and who were behind d'Erlon—and the Chasseurs of the Guard, supported by an incessant fire from the infantry of General Lefebvre-Desnoettes, dashed across the plain beyond the farm of La Haye Sainte. The advance of eight regiments and four brigades of their formidable horsemen created a great sensation, as it was believed the final moment was come. As General Milhaud passed before Lefebvre-Desnoettes, he grasped his hand and said, "I am going to charge, support me!" The commander of the light cavalry of the Guard believed it was by order of the Emperor he was desired to support the cuirassiers, and following their movement he took up a position behind them. It was Ney's belief, as he had said to Druot, that were he allowed to act he could, unaided, with such a body of noble cavalry at his disposal, now put an end to the English army.
A fierce struggle ensued in which Ney had some advantage over the English, but not what had been expected. He now hastened towards Lefebvre-Desnoettes, made a signal to advance, and precipitated him on the Duke of Wellington's English and German cavalry. This charge allowed the somewhat disorganized cuirassiers time to form again, and they, with the chasseurs and lancers, fell again upon the English cavalry. Thousands of hand-to-hand conflicts now were in progress, ending in the enemy retreating behind the squares of the English infantry, thus stopping the onward progress of the French horsemen.
Ney had two horses killed under him, but he was still determined to fulfill his vow to break the English lines. Observing now, on the other side of the plateau, 3,000 cuirassiers and 2,000 mounted grenadiers of the Guard that had not been yet engaged, the Marshal asked that they be given him to complete the victory.