One of the most realistic pictures of the fight at this stage is given by Captain Mercer, in command of a battery of horse artillery. Mercer was on the extreme British right during the first stage of the battle, and only got occasional glimpses of the ridge where the fight was raging--intermittent visions of French cavalry riding in furious charges, and abandoned British batteries with guns, muzzle in air, against the background of grey and whirling smoke. About three o'clock, in the height of the cavalry struggle, Fraser, who was in chief command of the horse artillery, galloped down the reverse slope to Mercer's battery, his face black with powder, his uniform torn, and brought the troop at full gallop to the central ridge, explaining as they rode the Duke's orders, that, when the French cavalry charged home, Mercer and his men should take refuge under the bayonets of the nearest square. As they neared the crest at a gallop, Mercer describes the humming as of innumerable and gigantic gnats that filled the bullet-torn air. He found his position betwixt two squares of Brunswickers, in whose ranks the French guns were making huge gaps, while the officers and sergeants were busy literally pushing the men together. "The men," says Mercer, "were like wooden figures, semi-paralysed with the horrors of the fight about them;" and to have attempted to run to them for shelter would certainly have been the signal for the whole mass to dissolve. Through the smoke ahead, not a hundred yards distant, were the French squadrons coming on at a trot. The British guns were swung round, unlimbered, loaded with case-shot, and fire opened with breathless speed. Still the French came on; but as gun after gun came into action, their pace slowed down to a walk, till the front files could endure the terrific fire no longer. They turned round and tried to ride back. "I actually saw them," says Mercer, "using the pommels of their swords to fight their way out of the _melee_." Some, made desperate by finding themselves penned up at the very muzzles of the British guns, dashed through their intervals, but without thinking of using their swords. Presently the mass broke and ebbed, a flood of shattered squadrons, down the slope. They rallied quickly, however, and their helmets could be seen over the curve of the slope as the officers dressed the lines.