As both armies face each other, Welligton uses the cover of the hill to avoid the French 'Grand Battery'. "At 11:00, Napoleon drafted his general order. Jerome's corps would make an initial attack on Hougoumont, which Napoleon expected would draw in Wellington's reserves, since its loss would threaten his communications with the sea. A grande batterie of the reserve artillery of I, II, and VI Corps was to bombard the centre of Wellington's position from about 13:00. D'Erlon's corps then would attack Wellington's left, break through, and roll up his line from east to west. In his memoirs, Napoleon wrote that his intention was to separate Wellington's army from the Prussians and drive it back towards the sea."
http://en.wikipedia.org/wiki/Battle_of_Waterloo#Hougoumont
From the movie Waterloo.
