[3] Surely an error in judgment, for thus the whole mass of the army, all of it except the First and Second Corps, would be crossing the Sambre at that one place, with all the delay such a plan would involve. As a fact, the Fourth Corps, or right wing of the advance, was at last sent over the river by Châtelet, but it would have been better to have given such orders at the beginning. [4] There were some five hundred Prussian prisoners. [5] See _ante_, pp. 27 and 32. [6] A lengthy digression might here be admitted upon the question of how defence against aerial scouting will develop. That it will develop none can doubt. Every such advantage upon the part of one combatant has at last been neutralised by the spread of a common knowledge and a common method to all. [7] To be accurate, not quite five-twelfths. [8] It is worth remarking that Perponcher had been told by Wellington, when he first heard of Napoleon's approach, to remain some miles off to the west at Nivelles. Wellington laboured, right up to the battle of Waterloo, under the fantastic impression that the French, or a considerable body of them, were, for some extraordinary reason, going to leave the Brussels road, go round westward and attack his _right_. He was, as might be expected of a defensive genius, nervous for his communications. Luckily for Wellington, Perponcher simply disobeyed these orders, left Nivelles before dawn, was at Quatre Bras before sunrise, and proceeded to act as we shall see above. [9] Or at the most sixteen. [10] This first division of the Guards consisted of the two brigades of Maitland and of Byng. [11] Let it be remembered, for instance, that Ziethen's corps, which helped to turn the scale at Waterloo, two days later, only arrived, on the field of battle _less than half an hour before sunset_. [12] I have in this map numbered separate corps and units from one to ten, without giving them names. The units include the English cavalry and Dornberg's brigade, with the Cumberland Hussars, the First, Second, Third, and Fifth Infantry Divisions, the corps of Brunswick, the Nassauers, and the Second and Third Netherlands Divisions. All of these ultimately reached Quatre Bras with the exception of the Second Infantry Division. [13] In which 15,000, as accurate statistics are totally lacking, and the whole thing is a matter of rough estimate, we may assign what proportion we will to killed, to wounded, and to prisoners respectively. [14] The reason he was thus ignorant of what had really happened to the Prussians was, that the officer who had been sent by the chief of the Prussian staff to the Duke after nightfall to inform him of the Prussian defeat had never arrived. That officer had been severely wounded on the way, and the message was not delivered.