Commencing the action according to his usual system, Napoleon kept his guard in reserve, in order to take opportunity of charging with them, when repeated attacks of column after column, and squadron after squadron, should induce his wearied enemy to show some symptoms of irresolution. But Napoleon's movements were not very rapid. His army had suffered by the storm even more than the English, who were in bivouac at three in the afternoon of the 17th June; while the French were still under march, and could not get into line on the heights of La Belle Alliance until ten or eleven o'clock of the 18th. The English army had thus some leisure to take food, and to prepare their arms before the action; and Napoleon lost several hours ere he could commence the attack. Time was, indeed, inestimably precious for both parties, and hours, nay, minutes, were of importance. But of this Napoleon was less aware than was the Duke of Wellington.
The tempest which had raged with tropical violence all night, abated in the morning; but the weather continued gusty and stormy during the whole day. Betwixt eleven and twelve, before noon, on the memorable 18th June, this dreadful and decisive action commenced, with a cannonade on the part of the French, instantly followed by an attack, commanded by Jerome, on the advanced post of Hougomont. The troops of Nassau, which occupied the wood around the chateau, were driven out by the French, but the utmost efforts of the assailants were unable to force the house, garden, and farm offices, which a party of the guards sustained with the most dauntless resolution. The French redoubled their efforts, and precipitated themselves in numbers on the exterior hedge, which screens the garden-wall, not perhaps aware of the internal defence afforded by the latter. They fell in great numbers on this point by the fire of the defenders, to which they were exposed in every direction. The number of their troops, however, enabled them, by possession of the wood, to mask Hougomont for a time, and to push on with their cavalry and artillery against the British right, which formed in squares to receive them. The fire was incessant, but without apparent advantage on either side. The attack was at length repelled so far, that the British again opened their communication with Hougomont, and that important garrison was reinforced by Colonel Hepburn and a body of the guards.