The fugitive Boers made northwards in the Middelburg direction, while Buller advanced to Standerton, which town he continued to occupy until Lord Roberts could send a force down through Heidelberg to join hands with him. Such was the position of the Natal Field Force at the end of June. From the west and the south-west British forces were also converging upon the capital. The indomitable Baden-Powell sought for rest and change of scene after his prolonged trial by harrying the Boers out of Zeerust and Rustenburg. The forces of Hunter and of Mahon converged upon Potchefstroom, from which, after settling that district, they could be conveyed by rail to Krugersdorp and Johannesburg.
Before briefly recounting the series of events which took place upon the line of communications, the narrative must return to Lord Roberts at Pretoria, and describe the operations which followed his occupation of that city. In leaving the undefeated forces of the Free State behind him, the British General had unquestionably run a grave risk, and was well aware that his railway communication was in danger of being cut. By the rapidity of his movements he succeeded in gaining the enemy's capital before that which he had foreseen came to pass; but if Botha had held him at Pretoria while De Wet struck at him behind, the situation would have been a serious one. Having once attained his main object, Roberts could receive with equanimity the expected news that De Wet with a mobile force of less than two thousand men had, on June 7th, cut the line at Roodeval to the north of Kroonstad. Both rail and telegraph were destroyed, and for a few days the army was isolated. Fortunately there were enough supplies to go on with, and immediate steps were taken to drive away the intruder, though, like a mosquito, he was brushed from one place only to settle upon another.
Leaving others to restore his broken communications, Lord Roberts turned his attention once more to Botha, who still retained ten or fifteen thousand men under his command. The President had fled from Pretoria with a large sum of money, estimated at over two millions sterling, and was known to be living in a saloon railway carriage, which had been transformed into a seat of government even more mobile than that of President Steyn. From Waterval-Boven, a point beyond Middelburg, he was in a position either to continue his journey to Delagoa Bay, and so escape out of the country, or to travel north into that wild Lydenburg country which had always been proclaimed as the last ditch of the defence. Here he remained with his gold-bags waiting the turn of events.
Botha and his stalwarts had not gone far from the capital. Fifteen miles out to the east the railway line runs through a gap in the hills called Pienaars Poort, and here was such a position as the Boer loves to hold. It was very strong in front, and it had widely spread formidable flanking hills to hamper those turning movements which had so often been fatal to the Boer generals. Behind was the uncut railway line along which the guns could in case of need be removed. The whole position was over fifteen miles from wing to wing, and it was well known to the Boer general that Lord Roberts had no longer that preponderance of force which would enable him to execute wide turning movements, as he had done in his advance from the south. His army had decreased seriously in numbers. The mounted men, the most essential branch of all, were so ill horsed that brigades were not larger than regiments. One brigade of infantry (the 14th) had been left to garrison Johannesburg, and another (the 18th) had been chosen for special duty in Pretoria. Smith-Dorrien's Brigade had been detached for duty upon the line of communications. With all these deductions and the wastage caused by wounds and disease, the force was in no state to assume a vigorous offensive. So hard pressed were they for men that the three thousand released prisoners from Waterval were hurriedly armed with Boer weapons and sent down the line to help to guard the more vital points.