Napoleon, when he had inspected all this and assured himself that Wellington was standing ranged upon the opposite ridge, returned to sleep an hour or two at the farm called Le Caillou, a mile behind the line of bivouacs. Wellington took up his quarters in the village of Waterloo, about a mile and a half behind the bivouacs of his troops upon the Mont St Jean.
In such a disposition the two commanders and their forces waited for the day.
There must, lastly, be considered, before the description of action is entered on, the nature of the field upon which it was about to be contested. That field had been studied by Wellington the year before. He, incomparably the greatest tactical defensive commander of his time, and one of the greatest of all time, had chosen it for its capacities of defence. They were formidable. Relying upon them, and confident of the Prussians coming to his aid when the battle was joined, he rightly counted upon success.
Let us begin by noting that of no battle is it more important to seize the exact nature of the terrain, that is, of the ground over which it was fought, than of Waterloo.
To the eye the structure of the battlefield is simple, consisting essentially of two slight and rounded ridges, separated by a very shallow undulation of land.
But this general formation is complicated by certain features which can only be grasped with the aid of contours, and these contours, again, are not very easy to follow at first sight for those who have not seen the battlefield.
In the map which forms the frontispiece of this volume, and to which I will beg the reader to turn, I have indicated the undulations of land in pale green lines underlying the other features of the battle, which are in black, red, and blue. The contours are drawn at five metres (that is 16 feet 4 inches) distance; no contours are given below that of 100 metres above the sea. The valley floors below that level are shaded. Up to the 120-metre line the contours are indicated by continuous lines of increasing thickness. Above the 120-metre line they are indicated by faint dotted or dashed lines. I hope in this manner, though the task is a difficult one, to give a general impression of the field.
The whole field, both slight ridges and the intervening depression, lies upon a large swell of land many square miles in extent, while it slopes away gradually to the east on one side and the west on the other. The highest and hardly distinguishable knolls of it stand about 450 feet above the sea. The site of the battle lies actually on the highest part, the water-parting; and the floors of the valleys, down which the streams run to the east and to the west, are from 150 to 200 feet lower than this confused lift of land between. To one, however, standing upon any part of the battlefield, this feature of height is not very apparent. True, one sees lower levels falling away left and right, and the view seems oddly wide, but the eye gathers the impression of little more than a rolling plain. This is because, in comparison with the scale of the landscape as a whole, the elevations and depressions are slight.