four days: the breakdown of Napoleon's last desperate venture turned
upon Erlon's useless marching and countermarching between Quatre Bras and
Ligny, two days before the final action of Waterloo was fought.

This being so, the battle of Waterloo must resolve itself into two main
phases: the first, the beginning of the struggle with Wellington before
the Prussians come up; the second, the main and decisive part of the
action, in which both Prussians and English are combined against the
French army.

This second phase develops continually as the numbers of the arriving
Prussians increase, until it is clinched by the appearance of Ziethen's
corps at the very end of the day, and the break-up of the French army;
this second part is therefore itself capable of considerable subdivision.
But in any large and general view of the whole action, we must regard it
as divided into these two great chapters, during the first of which is
engaged the doubtful struggle between Napoleon and Wellington; during the
second of which the struggle, no longer doubtful, is determined by the
arrival of the Prussians in flank upon the field.

[Illustration: ELEMENTS OF WATERLOO.]

THE FIRST PART OF THE ACTION

_Before the Arrival of the Prussians_

The action was to take the form of an assault by Napoleon's forces against
this defensive position held by Wellington. It was the business of
Wellington, although his total force was slightly inferior to the enemy in
numbers,[17] and considerably inferior in guns, to hold that defensive
position until the Prussians should come up in flank. This he had had word
would take place at latest by one or two o'clock. It was the business of
Napoleon to capture the strong outworks, Hougomont and La Haye Sainte;
and, that done, to hammer the enemy's line until he broke it. That delay
in beginning this hammering would be fatal; that the Prussians were
present upon his flank, could arrive in the midst of the battle, and were
both confidently and necessarily expected by his enemy; that his simple
single battle would turn into two increasingly complex ones, Napoleon
could have no idea. Napoleon could see no need for haste. A long daylight
was before him. It was necessary to let the ground dry somewhat after the
terrible rain of the day before if artillery was to be used effectively;
nor did he press his columns, which were moving into position all through
the morning, and which had not completely deployed even