The demoralization was, however, confined to the burghers who had been fighting on the Modder River. The commandos which had been opposed to Gatacre, Clements, and Brabant in the Cape Colony retired across the Orange in good order under Olivier, Lemmer, and E.R. Grobler; and although encumbered by lengthy trains of ox-wagons, marched up the right bank of the Caledon along the Basuto Border, and established themselves with a strength of 6,000 burghers on Lord Roberts' right flank near Ladybrand and Clocolan: a daring exploit which was justified by its success, as the left flank throughout the trek was exposed to a raid from Bloemfontein or Edenburg. A mounted force 1,800 strong under French was indeed sent eastward to show the flag, detach the waverers, and if possible, intercept the retreat; but the information at Head Quarters was imperfect and the strength of the commandos was greatly underestimated. It was assumed that they had been subject to the disintegration which obliterated the Modder River commandos; but a small reconnoitring column, detached under Pilcher by French from Thabanchu, found itself in presence of a force which outnumbered it thirty times, and was recalled. The presence of a considerable body of the enemy organized on the flank, the necessity of accumulating a large stock of supplies and stores, and a serious epidemic of fever among the troops, postponed the advance on the Transvaal many weeks beyond the end of March, when Lord Roberts had hoped to set out for the north. The apparent pacification of the country and the alacrity displayed by the burghers in submitting to the generous conditions of the proclamation of neutrality, had encouraged him in the belief that prompt action before the enemy had time to take breath would finally crush the dwindling opposition; but he soon became aware that it was but a lull in the storm, of which the mutterings were almost immediately renewed. Pole-Carew, who shortly after the occupation was sent south with a brigade to establish touch with Gatacre and Clements and open up the railway, heard of the Boer movement along the Basuto Border and at once reported it to Lord Roberts, whom he rejoined at Bloemfontein on March 17. Before the end of the month the line was cleared and trains were passing to and fro between Capetown and the capital of the Free State, which had lately been renamed the Orange River Colony. From that time forward the enemy succeeded on one occasion only, and then but for a few hours, in cutting the Springfontein-Bloemfontein railway; and the hazardous advance along the Modder River, which involved the possibility of the Army being left in the air at Bloemfontein, was fully justified.