Thus the allied cantonments extended for nearly 90 m. and their mean depth was 3o m. To concentrate on either flank would take six days, and on the common centre, Charleroi, three days.
The allies had foreseen the manoeuvre that Napoleon decided to adopt, and if an attempt was made to break their centre they intended to concentrate forwards and on their inner flanks, the Anglo-Dutch at Gosselies and the Prussians at Fleurus. They could then act united against Napoleon with a numerical superiority of two to one. They felt certain they would obtain the necessary three days' warning of the French concentration, as Napoleon's troops were then distributed between Lille, Metz and Paris (175 m. by 'co m.). To concentrate the French army, within striking distance of Charleroi, before the allies had moved a man to meet it was unthinkable. But it was the unthinkable that happened.
Whereas Blucher had covered Fleurus by Zieten's Corps, which by a yielding fight would secure the time for the Prussian con centration, yet Wellington had only covered Gosselies by a cavalry screen which was too weak to gain the time requisite for the Duke to mass there. Hence to enable him to concentrate as arranged Wellington relied on obtaining timely information of Napoleon's plans, which in fact he failed to obtain.
The French Concentration.—The emperor made his final preparations with the utmost secrecy. The "Armee du Nord" was to concentrate in three columns—around Solre, Beaumont and Philippeville—as close to Charleroi as was practicable. On June 6 the IV. Corps (Gerard) started and soon the whole army was in motion, every effort being made to hide the movements of the troops, for there was no great natural screen to cover the strategical concentration. On June I I Napoleon left Paris for the front, and by June 14 he had achieved almost the impossible itself. There around Solre, Beaumont, and Philippeville lay his mass of men, 124,00o, concentrated under his hand and ready to march across the frontier at dawn against the unsuspicious enemy. The allies still lay in widely distant cantonments and they had not moved a man to meet the foe.
ton's was a collection of many nationalities, and the kernel of British and King's German Legion troops numbered only 42,00o. BlUcher's army was undoubtedly more homogeneous and included no specially weak elements. Napoleon led out a veteran army of Frenchmen who worshipped their leader. But there were lines of weakness in his force. For various reasons, neither Davout, Murat, Suchet, nor Clausel were employed in the "Armee du Nord." Marshal Soult, appointed chief of the staff, possessed few qualifications for this post ; and neither Ney nor Grouchy who, when the campaign began were given command of the left and right wings, possessed the ability or strategic skill necessary for such positions. Again the army was morally weakened by a haunting dread of treason; and, finally, it was too small for its purpose. Locked up in secondary theatres Napoleon had left 56,500 men, of whom he might have collected over 30,00o for the decisive campaign in Belgium. Had he concentrated 155,000 of his available force opposite to Charleroi on June 14, then the issue would hardly have been in doubt. As it was he left too much to Fortune.
For his advance into Belgium in 1815 Napoleon divided his army into two wings and a reserve. As the foe would lie away to his right and left front after he had passed the Sambre, one wing would be pushed up towards Wellington and another towards Blucher; whilst the mass of the reserve would be centrally placed so as to strike on either side, as soon as a force of the enemy worth destroying was encountered and gripped. To this end he had, on the 14th, massed his left wing (Reille and D'Erlon) around Solre, and his right wing (Gerard) at Philippeville; whilst the central mass (Vandamme, Lobau, the Guard and the Cavalry Reserve) lay around Beaumont. The orders for the French ad vance next day, among the finest ever issued, directed that the army should march at dawn and move to the Sambre at Mar chienne and Charleroi. By evening it was expected that the whole would have crossed the Sambre, and would bivouac between the sundered allies.