On the morning of January 23, Buller saw Warren, and again pressed him to make an attack on the Boer right; but finding that the orders for the assault on Spion Kop had already been issued, he refrained from vetoing it. He threatened, however, that if immediate action in some direction were not taken, Warren's force would be withdrawn to the south of the Tugela.
On the previous day Warren, betraying the Engineer officer unused to handling large bodies of men, and unfamiliar with the military unities, rearranged his command with a straight edge, and distributed it in one way for tactical, and in another for administrative purposes. All the troops lying west of an imaginary line became the left attack under Clery, while those east of it became the right attack. The latter, under Talbot Coke, were ordered to seize the Spion Kop position by night, and entrench it before daybreak, the actual assault being made by Woodgate with two battalions, some mounted infantry on foot, and a few Engineers. At sunset on January 23, the curtain fell upon the first act of the Tragedy of Spion Kop.
On the night of the January 23 Spion Kop was held as an observation post by a party of seventy burghers. When Buller first appeared at Potgieter's Drift, it was on the right of the Boer line, but now it was only the right of the centre under Schalk Burger. Little was known of its features and tactical value, beyond the information obtainable by a telescopic reconnaissance. It was a prominent object in the Boer position, and it seemed to be within the grasp of a night adventure. Woodgate left his rendezvous at 9 p.m., but it is doubtful whether he would have reached the summit before daybreak but for Thorneycroft, who was in command of the mounted infantry which bore his name, and who had before nightfall picked out and noted the recognizable objects on the slope. A staff officer from Head Quarters, who accompanied the column to direct the march, had had no opportunity of making himself acquainted with the way of access to Spion Kop, and Thorneycroft was ordered to act as guide.
The summit, but fortunately little more than the summit, was veiled in mist, and the crest was reached. Bayonets were fixed before the Boer picket was alarmed and opened fire, but the ammunition was spent without effect, as Thorneycroft's men had by order thrown themselves on the ground as soon as they were discovered. A charge into the mist drove back the picket and scared the main body off the summit. Thus before dawn on January 24, Warren was in possession of the hill which was believed to be the key of the Boer position, and the chief obstacle in the way of his advance seemed to be thrust aside: but the mist on Spion Kop was the forecast of the Fog of War which was soon to envelope him.
Woodgate, having the men, the tools and the ground, at once began impulsively to dig, without endeavouring to inform himself of the features of the position he had so easily won. A sort of a trench had been scratched on the summit by the weary men, when the mist rolling away for a little while disclosed the startling topography of the position. The surface of the plateau sloped gently at first, and then abruptly fell away, and the trench was found to be of little use. The enemy could approach on dead ground to within two hundred yards of it. Woodgate, seeing that the real defensible line was not the highest part of the summit, but the edge lower down, where the steep descent began, sent working parties to the front, but they at once came under fire. Soon the mist again enveloped the hill, and having disposed his force, he reported to Warren that he had established himself on Spion Kop.
The Boer outpost which had been driven from the summit belonged to Schalk Burger's command. With Botha's co-operation a storming force was soon brought together, and almost every point from which Spion Kop could be brought under fire was seized, even the Little Knoll near the summit, which enfiladed the main trench. Joubert telegraphed from Ladysmith that the position must be re-captured, and Kruger at Pretoria asked what was being done to win it back.
Little did Woodgate's force realize what the morning mist was hiding. Soon after 8 a.m. the sun dissolved the veil, and the storm burst. From the right the men in the trench and lower crest were enfiladed by the Little Knoll and the Twin Peaks; on their front and left they were rained on by bullet and shrapnel from Conical Hill, Green Hill, and beyond; with such effect that the lower crest had to be temporarily abandoned. Woodgate was soon mortally wounded and the command devolved upon Crofton. Spion Kop was the first position of great tactical importance won by the British Army on the Tugela, and the Boers were determined to recover it.
The naval guns posted on Mount Alice and at Potgieter's Drift opened fire not only on the Little Knoll near the Spion Kop plateau and on the Twin Peaks, but were also pitching their shells over the summit on to the Boer positions supposed to be in line with it, and a field battery on Three Tree Hill shelled the open ground on which the enemy was advancing.