By nine o'clock it was dark and the action ceased. Just as it ceased, and while, in the last glimmerings of the light, the major objects of the landscape, groups of wood and distant villages, could still be faintly distinguished against the background of the gloom, one such object seemed slowly to approach and move. It was first guessed and then perceived to be a body of men: the head of a column began to debouch from Frasnes. It was Erlon and his 20,000 returned an hour too late.
All that critical day had passed with the First Corps out of action. It had _neither_ come up to Napoleon to wipe out the Prussians at Ligny, _nor_ come back in its countermarch in time to save Ney and drive back Wellington at Quatre Bras. It might as well not have existed so far as the fortunes of the French were concerned, and its absence from either field upon that day made defeat certain in the future, as the rest of these pages will show.
Two things impress themselves upon us as we consider the total result of that critical day, the 16th of June, which saw Ney fail to hold the Brussels road at Quatre Bras, and there to push away from the advance on Brussels Wellington's opposing force, and which also saw the successful escape of the Prussians from Ligny, an escape which was to permit them to join Wellington forty-eight hours later and to decide Waterloo.
The first is the capital importance, disastrous to the French fortunes, of Erlon's having been kept out of both fights by his useless march and countermarch.
[Illustration: THE ELEMENTS OF QUATRE BRAS.]
The second is the extraordinary way in which Wellington's command came up haphazard, dribbling in by units all day long, and how that command owed to Ney's caution and tardiness, much more than to its own General's arrangements, the superiority in numbers which it began to enjoy from an early phase in the battle.
I will deal with these two points in their order.
The whole of the four days of 1815, and the issue of Waterloo itself, turned upon Erlon's disastrous counter-marching between Quatre Bras and Ligny upon this Friday, the 16th of June, which was the decisive day of the war.
What actually _happened_ has been sufficiently described. The useless advance of Erlon's corps d'armée towards Napoleon and the right--useless because it was not completed; the useless turning back of that corps d'armée towards Ney and the left--useless because it could not reach Ney in time,--these were the determining factors of that critical moment in the campaign.