Well might Prince Karl think his position altogether unassailable, and believe that, if the Prussians were mad enough to attack, they would be destroyed. Frederick and Schwerin spent much time in surveying the position, and agreed that on two sides the Austrian position was absolutely impregnable; but that on the right flank, attack was possible. Schwerin would fain have waited until the next morning, since his troops were fatigued by their long marches, and had been on foot since midnight. The Austrians, however, were expecting a reinforcement of thirty thousand men, under Daun, to join them hourly; and the king therefore decided on an attack, the terrible obstacles presented by the swamps being altogether unnoticed.

With incredible speed the Prussians moved away to their left, and by eleven o'clock were in readiness to attack the right flank of the Austrian position. Browne, however, was in command here and, as soon as the intention of the Prussians was perceived, he swung back the right wing of the army at right angles to its original position, so that he presented a front to the Prussian attack; massing thickly at Sterbold, a village at the edge of the swamps. Rapidly the whole of the artillery and cavalry were formed up on this face and, quick as had been the advance of the Prussians, the Austrians were perfectly ready to meet them.

Led by General Winterfeld, the Prussians rushed forward; but as they advanced, a terrific artillery fire was opened upon them. Winterfeld was wounded severely, and the troops fell back.

The main body now advanced, under Schwerin, and the whole again pressed forward. In spite of the incessant rain of grape and case shot, the Prussians advanced until they reached the pleasant green meadows they had seen in the distance. Then the real nature of the ground was at once disclosed.

The troops sunk to the knee, and in many cases to the waist, in the treacherous mud. Soldiers less valiant and less disciplined would have shrunk, appalled at the obstacle; but the Prussians struggled on, dragging themselves forward with the greatest difficulty through mud, through slush, through a rain of grape from upwards of two hundred cannon, and through a storm of musketry fire from the infantry. Regiment after regiment, as it reached the edge of the dismal swamp, plunged in unhesitatingly, crawling and struggling onward.

Never in the annals of warfare was there a more terrible fight. For three hours it continued, without a moment's interval. Thousands of the assailants had fallen, and their bodies had been trodden deep into the swamp, as their comrades pressed after them. Sometimes a regiment struggled back out of the mire, thinking it beyond mortal power to win victory under such terms; but the next moment they reformed and flung themselves into the fight again. Schwerin, seeing the regiment named after him recoil, placed himself at their head; and shouting, "Follow me, my sons!" led them till he fell dead, struck by five grape shot.

The Austrians fought as stoutly, Marshal Browne leading them till a cannonball took off his foot, and he was carried into Prague, to die there six weeks later.

While this terrible struggle was going on, the Prussian cavalry had made a very wide circuit round the ponds and lakelets, and charged the Austrian horse on Browne's extreme right. The first lines were broken by it, but so many and strong were they that the Prussians were brought to a standstill. Then they drew back and charged a second, and a third time.

The Austrians gave way. Prince Karl himself, brave if incapable, did his best to rally them, but in vain; and at last they fled in headlong rout, pursued for many miles by Ziethen's horsemen.

Still the infantry struggle was maintained. At last the Prussian right wing, hitherto not engaged, though suffering from the artillery fire on the heights, had their turn. General Mannstein discovered that, at the angle where Browne threw back the right wing of the army to face the Prussians, there was a gap. The troops there had gradually pressed more to their right, to take part in the tremendous conflict; and the elbow was, therefore, defended only by a half-moon battery.