On June 13 Buller entered Volksrust and next day established his Head Quarters at Laing's Nek. Wakkerstroom, a town which threatened his right flank, surrendered _pro formâ_ to Lyttelton on June 13, and again to Hildyard four days later; and no doubt would have been equally ready to accommodate itself to the wishes of any other column sent to it, but after each surrender it reasserted itself, and Buller was obliged to leave it in charge of the commandos. With the occupation of Laing's Nek the Natal campaign, which had lasted eight months, came to an end, and Buller, having left a strong force under Lyttelton in charge of Natal, passed up the railway to Heidelberg; where on July 4 he for the first time came into physical touch with the main Army under Lord Roberts. By a curious coincidence he here met Hart's Brigade of the Xth Division, which had left his command three months previously at Ladysmith, and which had in the meantime marched up from Kimberley. [Sidenote: Map, p. 292.] Lord Roberts' plan for the Natal Army was that it should march across the veld to the Delagoa Bay railway and co-operate in his movement to clear the Eastern Transvaal. The Brandwater Basin surrender relieved the railway in Natal from immediate danger and allowed the ample force holding it to be reduced. At the end of July Buller was instructed to lead 11,000 of his men across a sparsely populated country where no railway was. It was for him a novel phase of warfare. Hitherto he had hardly dared trust himself out of sight of a culvert. But he was a man from whom the terror of the unknown very soon passed away when he had no choice but to face it. In Natal he would have stood aghast at a suggestion that he should cut away his moorings and be wafted by the winds of war for ten days or more across a strange ocean. If hitherto he had been _nec celer nec audax_ now he became at least _audax_. Lord Roberts had imbued him with the progressive spirit. He raised no difficulties of his own, and he encountered those arising out of the situation resolutely and successfully. His army was strung out upon the railway from Ladysmith to Heidelberg; his transport was still organized regimentally, a system which had hampered Lord Roberts' movements and was soon abolished in the main body; and oxen, mules, and wagons were scarce. For infantry he chose the IVth Division under Lyttelton, and for cavalry the brigades under Brocklehurst and Dundonald. On August 7 Buller's column quitted the Natal line;[48] its destination being Belfast on the Delagoa Bay line, along which Lord Roberts was now advancing. Its progress may be compared to the course of a steamer across an unquiet ocean. The waves raised by a fresh gale on the starboard bow were cleft by the stem, only to reunite behind the churn of the propeller. They were powerless to abridge the day's run by many miles, but they could still swing forwards to the shore. On one occasion the ship was slowed down to a standstill by a fog.