A new line of supply was opened on the 28th, when Colonel Bullock started from Volkrust to Piet Retief with a convoy of ninety-one waggons. Though this reached its destination in safety on the 5th of March, it was not till he returned with a second load, on the 21st of March, that sufficient oats could reach Piet Retief to enable the force to move. Despite the inconvenience of delay a tremendous amount of work was carried on, the troops pushing continually into Swaziland and tackling Boers who struggled to slip through the British line, and many captures were made both north and south of the border. The surrounding country was thoroughly cleared, and many guns and much ammunition were brought to light. The Engineers also worked like Trojans, improving the roads and bridging the numerous, now swollen, rivers and spruits that abounded in the district. As an instance of the force of the unceasing floods between the 6th and 13th of March, it may be mentioned that the Assegai, which is normally fordable, averaged 12 feet in depth, and on the 12th rose to 18 feet. [Illustration: A NIGHT ATTACK: DEFENDING A TRAIN DERAILED BY THE BOERS Drawing by Frank Dadd, R.I.] The position of the forces on the 1st of March stood thus:-- General Smith-Dorrien (who had moved south from Amsterdam on the 25th of February) was now eight miles north of Piet Retief, while his mounted troops, under Colonel Henry, had penetrated into Swaziland. At Piet Retief was General French, with Colonels Knox and Pulteney, some of whose mounted troops, under Colonel Rimington, were covering the road south-west of Luneberg as far as Schihoek, whence Colonel Burn-Murdoch carried on the line to Utrecht. Colonels Campbell and Allenby were twelve and seventeen miles south-east of Piet Retief respectively, Colonel Alderson was at Marienthal, and General Dartnell at Intombi River. Colonel Bullock was at Wakkerstroom. Soon the Utrecht-Luneberg line was abandoned as a line of supply, and the troops were based on Utrecht. On the 18th of March General Dartnell occupied the village of Paul Pietersburg, and Colonel Rimington seized the stone bridge over the Pivaan River running south of it, while Colonel Alderson built a pontoon bridge over the Pongola River at Yagd Drift. On the 21st General French, with Colonels Knox and Pulteney, moved on, leaving General Smith-Dorrien in command north of the Pongola. Here the latter, with the columns of Colonels Campbell and Allenby, held a line from Langdraai Drift, in the Lower Pongolo, by Platnek, Mahamba, Zaudbauk, and Piet Retief, to Yagd Drift, so as to prevent Boers from breaking north and north-west.