officer who thought he was rightly interpreting Napoleon's wishes. Ney, on hearing what had happened, very properly recalled D'Erlon: his orders were to dislodge the English from Quatre-Bras, which he could not do without D'Erlon's troops, and then, but not till then, to reinforce Napoleon. The result however was that D'Erlon's corps wasted the day in marching to and fro, and took part in neither battle, though its active co-operation ought to have been decisive on either field. Sunset was approaching, and Napoleon, seeing that it was too late to send effective orders after D'Erlon, made his attack on the Prussian centre as before arranged. Its success gave him an undoubted victory, but dearly bought, and not overwhelming. The Prussians were able to retreat unmolested under cover of the darkness, leaving behind them over 20,000 men, killed, wounded and prisoners, or about a third of the two corps, Ziethen's and Pirch's, on which the stress of the fighting had fallen. The French army bivouacked on the field how they could: their loss had amounted to 11,000 or 12,000 men. Thus up to nightfall on June 16 Napoleon had gained considerable success. He had attained his first object, of engaging and defeating Blucher before Wellington could come to his assistance, and might reasonably expect to attain his second object, of attacking Wellington with his main force while separated from the Prussians, in which case with a superior army he ought to win a decisive victory. That more had not been achieved was due to the delay on the French left, which neutralised the advantage resulting from Wellington's undue slowness in concentrating his army. As often happens in war, one mistake but cancelled the other. On the 17th most part of the advantage which the French possessed over the allies was lost, largely by Napoleon's own fault, partly by the loyal co-operation of Blucher and Wellington. Critics who treat war like a game of chess, and forget that soldiers are men who must eat and sleep, say that Napoleon ought to have started at daybreak, to take Wellington at Quatre-Bras in flank, while Ney renewed the attack in front. But the emperor himself was exhausted by two extremely long and fatiguing days: nor could even the troops that had taken but little part in a battle ending at 9.30 p.m. be expected to be in marching order again in six hours. Napoleon made the grievous mistake of taking for granted two things, both of them likely, but neither of them in fact true. First he more or less assumed that Wellington, informed of the result of the battle of Ligny, would have retreated, leaving only a rearguard at Quatre-Bras; if this were so, there was no use in Napoleon's trying to attack him. As a matter of fact, Wellington did not receive the news of Ligny till the morning of the 17th, and he then waited to exchange communications with Blucher before ordering a retreat, for which there was no immediate hurry, unless the French resumed the offensive.