Lieuts. Chard and Bromhead now saw that their lines of defence were too large for the number of men left to them, and at once began the erection of an inner entrenchment formed of biscuit boxes taken from the stores. When this wall was but two boxes high, suddenly there appeared five or six hundred Zulus advancing at a run against the southern side of their position. These were soldiers of the Undi regiment, the same that had turned the Isandhlwana mountain, cutting off all possibility of retreat by the waggon road, who, when they knew that the camp was taken, had advanced to destroy the guard of Rorke's Drift. On they came, to be met presently by a terrible and concentrated fire from the Martinis. Many fell, but they did not stay till, when within 50 yards of the wall, the cross fire from the store took them in flank. Their loss was now so heavy that, checking their advance, some of them took cover among the ovens, cookhouse, and outbuildings, whence they in turn opened fire upon the garrison. Hundreds more rushing round the hospital came at full speed against the north-west fortification of sacks filled with corn. In vain did the Martinis pump a hail of lead into them: on they came straight to the frail defence, striving to take it at the point of the assegai. But here they were met by British bayonets and a fire so terrible that even the courage of the Zulus could not prevail against it, and they fell back, that is, those of them who were left alive. By this time the main force of the Undi had arrived, two thousand of them, perhaps, and having lined an overlooking ledge of rocks, took possession of the garden of the station and the bush surrounding it, from all of which the fire, though badly directed, was so continuous that at length the little garrison of white men were forced back into their inner entrenchment of biscuit boxes. Creeping up under cover of the bush, the Zulus now delivered assault after assault upon the wall. Each of these fierce rushes was repelled with the bayonets wielded by the brave white men on its further side. The assegais clashed against the rifle barrels, everywhere the musketry rang and rolled, the savage war-cries and the cheers of the Englishmen rose together through the din, while British soldier and Zulu warrior thrust and shot and tore at each other across the narrow wall, that wall which all the Undi could not climb.