]

To the present writer it seems probable that Gneisenau's action, in
the first instance, was undertaken as the readiest means of reuniting
the Prussian wings. But Gneisenau cannot have been blind to the
advantages of a reunion with Wellington, which a northerly march would
open out. The report which he sent to his Sovereign from Wavre shows
that by that time he believed the Prussian position to be "not
disadvantageous"; while in a private letter written at noon on the
17th he expressly states that the Duke will accept battle at Waterloo
if the Prussians help him with two army corps. Gneisenau's only doubts
seem to have been whether Wellington would fight and whether his own
ammunition would be to hand in time. Until he was sure on these two
points caution was certainly necessary.

The results of this prompt rally of the Prussians were infinitely
enhanced by the fact that Wellington soon found it out, while Napoleon
did not grasp its full import until he was in the thick of the battle
of Waterloo. To the final steps that led up to this dramatic finale we
must now briefly refer.

It is strange that Gneisenau, on the night of the 16th, took no steps
to warn his allies of the Prussian retreat, and merely left them to
infer it from his last message, that he must do so if he were not
succoured. Mueffling, indeed, says that a Prussian officer was sent,
but was shot by the French on the British left wing. Seeing, however,
that Wellington had beaten back Ney's forces before the Prussian
retreat began, the story may be dismissed as a lame excuse of
Gneisenau's neglect.[498]

From the risk of being crushed by Napoleon, the Anglo-Dutch forces
were saved by the vigilance of their leader and the supineness of the
enemy. After a brief rest at Genappe, the Duke was back at the front
at dawn, and despatched two cavalry patrols towards Sombref to find
out the results of the battle. The patrol, which was accompanied by
the Duke's aide-de-camp, Colonel Gordon, came into touch with the
Prussian rear. On his return soon after 10, the staff-officer, Basil
Jackson, was at once sent to bid Picton immediately prepare to fall
back on Waterloo, an order which that veteran received very
sulkily.[499] Shortly after Gordon's return, a Prussian orderly
galloped up and confirmed the news of their retreat, which drew from
the Duke the remark: "Bluecher has had a d---- d good licking and gone
back to Wavre.... As he has gone back, we must go too."