But French did not complete his first day's work very auspiciously. His supply column was far behind when he reached Ramdam, and owing to a misunderstanding Hannay's Brigade of Mounted Infantry from Orange River, which was instructed to join him, did not turn up: conflicting orders had resulted as usual, ordre, contr'ordre, désordre. French, however, felt himself strong enough to continue his march without Hannay, who, on his delayed march to Ramdam, engaged a detached body of Boers and thereby strengthened the enemy's conviction that Koffyfontein was the objective.
As French approached the river, Waterval Drift, the lower of the two drifts across the Riet, was found to be occupied by De Wet, and the Division was diverted to De Kiel's Drift, which was reached without much difficulty at midday, February 12. On the right bank were the commando of the Jacobsdaal garrison under Lubbe, and the commando under De Wet and A.P.J. Cronje which had been sent to observe the cavalry movement; about 1,000 men in all. But De Wet could not get the Koffyfontein idea out of his head, and its influence removed many obstructions from the path of the advance. He boldly rode across French's front at De Kiel's Drift, and made S.E. for Winterhoek, closely followed by A.P.J. Cronje; and all French's horses could not find out where they had gone. Next day it was given out in Divisional Orders that the commandos had gone to the Modder River, and four weeks passed by before the Army ceased to suffer from the error.
There was still "one more river to cross" before the diamond men of Kimberley could be relieved; and ere the thirst of the South African summer could be slaked on the banks of the Modder, a tract of twenty-five miles of veld, in which the absence of any homestead having "fontein" for its suffix declared the scarcity of water, must be traversed under the sun.
In the forenoon of February 13 the Cavalry Division started northwards from De Kiel's Drift; and at last De Wet, who, unknown to French, was watching the trek from its right flank, partially relieved himself of the Koffyfontein idea. The effort weakened him, and he displayed none of that readiness of resource and promptitude of action with which he subsequently worried the British Army for the space of two years. He withdrew his own commando towards Koffyfontein, and having ordered Lubbe to follow French, reported to Cronje at Magersfontein that the cavalry was making for the Modder.
French's objective points were now Rondeval and Klip River Drifts on the Modder, but in order to deceive Lubbe, who was hanging on to his right flank, and to elbow him away from the drifts, French changed direction with two brigades and headed for Klip Kraal Drift, some eight miles above Klip Drift, reverting suddenly to his original line as soon as the river came in sight. The drifts were held by small parties of the enemy, who offered no resistance, and on the evening of February 13 the Division took possession of the kopjes on the north bank.
The occupation of the drifts was soon made known to Cronje, but the news revealed little to his dull and uninstructed nature, permeated with the idea that a British force and a railway were indissoluble entities. Though his communications eastward were now seriously threatened, it did not occur to him that there might be an alternative to fighting him out of Magersfontein, namely manoeuvring him out of it; and he persuaded himself that French's movement was a trap to entice him away pending an attack on Magersfontein from the south, and he was probably unaware that the relief of Kimberley was an urgent matter. He moved his own camp from Brown's Drift to a less exposed position at Bosjespan, and while retaining his hold on Magersfontein with his main body, sent out two commandos to watch French, and these accidentally occupied a line through which the cavalry must pass on its way to Kimberley.
The arrival of the VIth Division on the morning of February 15 set French free to resume his march on Kimberley. The two commandos had on the previous day joined hands with Lubbe, who, after he was pushed out of French's way, crossed the Modder at Klip Kraal Drift and worked round to a position north of Klip Drift. The relieving force was now obstructed in the line of its advance by ridges on its right and left fronts and by the nek connecting them, all occupied by the enemy; while on its left flank was Cronje's new camp at Bosjespan, of the existence of which it was unaware. The situation seemed awkward, as the only way out of it was the shallow valley leading up to the nek, and exposed to a converging fire from the ridges on which two guns were posted.
But French was not long in doubt, and like a bridge player who in order to win the game is sometimes compelled to assume the position of certain cards, with rare intuition correctly assumed that the nek was weakly held. Like a ship going down the ways to the water, the Division was launched to the front; cleaving the opposing waves and gaining momentum as it advanced, then righting itself, rose to the slope of the nek and carried it with resistless energy.
After a short midday halt at Abon's Dam, French raised the siege of Kimberley before sunset; the besiegers under Ferreira did not wait to be attacked, but withdrew towards Boshof.