Finding that touch had been satisfactorily established by Mackay with Woolls-Sampson on the right flank, and Leuchars on the left, McKenzie caused a small forest on Leuchars' side of the stream, and under high ground lined by his men, to be searched by Wilson's guns, using shrapnel. One squadron, N.C., lined the ridge on the right of Izinsimba, another was posted higher up the stream, whilst, as has been seen, a strong force was holding the ridge on Woolls-Sampson's left flank. By now, Woolls-Sampson had moved down the greater part of his column (dismounted) to block the Izinsimba valley more effectually, preparatory to driving up the stream, in which direction it was then evident the enemy was concealed and in force. After making such dispositions as were necessary, the drive began. Leuchars did not take part in the earlier movements that occurred near where the Indaka and Imbuyana streams enter the Izinsimba. What happened with his column was this: Arnott, with B.M.R. (two squadrons), and N.C. (D squadron), had been directed to occupy ground immediately opposite that held by Woolls-Sampson. Arnott's guide mistook the path, which resulted in his pushing too far down the Izinsimba, _i.e._ about 800 yards below Woolls-Sampson. Such position was reached at dawn. The error, however, proved advantageous, as the troops were just in time to prevent the escape of about 150 rebels who were between N.M.R. and B.M.R. They were driven up the Izinsimba and dealt with later. As, by this time (10.30 a.m.), it was clear that a considerable portion, if not the whole of Matshwili's _impi_ had been completely surrounded, McKenzie ordered the principal valley to be driven downwards towards Woolls-Sampson, whose men (N.M.R. and N.D.M.R.), then out of sight in the irregularly-shaped and bushy valley, were already slowly and cautiously driving upwards.[289] The former troops (_i.e._ those driving downwards) consisted of portions of Mackay's and Leuchars' columns acting in combination, notably N.C. and L. and Y. The drives, which were through rough and rocky country, took about three hours to complete. Two or three of the small, precipitous ravines opening into the main valley, especially on the right side of the stream, were also driven. During the drives, numerous armed rebels were come upon in various parts. These made the best use they could of their assegais and shields. There was plenty of cover, bushes as well as rocks, but before long the enemy realized that he had been completely hemmed in. He continued to fight to the last, though at considerable disadvantage, because of having broken up into small groups. The "Usutu" war-cry was used whenever any lot made up their minds to charge or hurl their assegais.