At noon on February 21 Buller began once more to send his men across the Tugela, intending to content himself that day with establishing his force "comfortably" on the position north of the railway bridge enclosed by the bend of the river, which was now free of the enemy. He ordered Talbot Coke with the 10th Brigade of Warren's Division to pass over the Colenso Kopjes on to the open ground beyond, from which the Onderbroek valley could be enfiladed by artillery. He had received information that the enemy were there in force, and in the belief that "what Boers there were, were hiding in that kloof," he changed his plan of moving northwards at once on Wynne's Hill. On February 21 Coke advanced in three lines, but soon after he had cleared the hilly ground, his scouting line came under fire from the Grobelaar slopes, and his right flank was also involved from the direction of Wynne's Hill. His Brigade was pinned to the ground by rifle and shell fire until nightfall, when it was retired to the Colenso Kopjes, where Wynne's Brigade of Warren's Division had arrived during the afternoon. [Illustration: Map of the Final Advance on Ladysmith.] The route march to Ladysmith was checked. Instead of a mere rearguard to be driven in, as Buller had fondly believed, a strongly posted line, extending nearly four miles S.W. from Wynne's Hill, had to be attacked. The enemy had been so much encouraged by the failure of Coke's movement, that Botha telegraphed to Kruger that he had hopes of a "great reverse." Warren thought that it would be necessary to diverge from the advance and take the Grobelaar slopes, and White reported that Boer reinforcements were coming in from the north. Towards evening on February 21, it seemed not unlikely that another Colenso, Spion Kop, or Vaalkrantz would soon be debited to Buller. The line of approach to Ladysmith was held by the enemy, and the British Army of relief, the greater part of which had crossed to the left bank of the Tugela, was entangled in the Colenso Kopjes, and the river loop. Warren's general idea for the 22nd, of which Buller approved, was to attack Wynne's Hill with the 11th Brigade, leaving Horseshoe Hill to be dealt with by the artillery. Although the Boers on the Grobelaar slopes had been well pounded for some hours by the field batteries, Wynne considered that it would be unsafe to advance unless these slopes were actually taken, but he was overruled. He had also been promised support on his left rear, but only two of the battalions detailed for the purpose were at hand and these were fully occupied in offering a front to the Boers on Grobelaar, while the movement was in progress; and he advanced against the enemy's centre unsupported except by the long range fire of a brigade on Naval Hill across the river.