AT the beginning of May 1900 Roberts advanced. Botha took up position after position to hold him back, but Roberts had now plenty of troops and without weakening his centre, which remained based on the railway, he felt for Botha's flanks and turned each position. With only a few skirmishes he took Kroonstad and was in front of Johannesburg. With his back up against the town and the mine stacks showing clearly close behind him, de la Rey took up a final position, but with little hope of holding the English off.
Smuts saw all he had worked to build up crumbling. All his calculations had proved incorrect. Military defeat had followed military defeat. The English were half across the Transvaal. The burghers were in a panic. All seemed lost. But these things, so far from making Smuts lose courage, made him set his jaw harder, and he became more determined and bitter. A sudden ruthless desire to destroy came on him. He decided to destroy the gold mines. The English had come for the gold: they should not get it so easily. He had proposed before to destroy them, but Botha had opposed him, and even threatened to resign if it was done, for he looked on it as a useless piece of wrecking; and Reitz had issued a public assurance that it would not be done. But he would do it now. The Assistant State Mining Engineer, Mr. Munnik, had prepared twenty-seven shafts and fitted them with dynamite charges in position. Smuts sent post-haste from Pretoria a Judge Koch with a party of men to do the wrecking before the English could march in. But the Commandant in Johannesburg was Judge Krause. Krause had often disagreed with Smuts before; he had not forgotten the blame passed on to him for the arrest of Monypenny: he disagreed with Smuts now and he promptly arrested Koch and his men. Roberts brushed de la Rey aside, marched into the town, took over the mines intact, and made straight for Pretoria.
Botha saw that it was impossible to hold the capital; the only line of retreat was down the Delagoa Railway into Portuguese East Africa: he would fight each stage of that. Kruger with Reitz and the rest of the Government made a run for it to.Machadodorp, a village a hundred miles farther down the same line,, and set up a new centre of government in some wagons in a siding. Smuts remained in Pretoria.
In Pretoria all was confusion. Burghers riding into the town, an undisciplined mob, convinced that the war was lost. There was looting and panic, no administration or control. The town was full of stores, munitions, and assets in cash and valuables. To give time to evacuate these, Botha collected some men and went out to check the English advance. Smuts with five hundred men marched out to Irene, but found the English were coming by another route and hurried back. Botha hurried away to prepare a position down the railway. The English were right on top of them, on their heels. There was no time to spare.
Hitherto Smuts had been the lawyer, his whole life based and bound on legal procedure, the interpretation of legal terms, his every action directed by its technical legality. Now, with office and papers gone, with his world torn up round him, he thrust legality out of his mind: he took direct action whether legal or not legal. To prevent the English getting anything of value he told the burghers to loot all they could and then to join up with Botha. There were cash and assets lying in the Treasury and in the banks. He demanded them. The officials refused unless he showed some legal authority. Smuts was standing no opposition, swept their demand on one side, took the money and assets out of the vaults, and, with volunteers and armed police, loaded them on a train in the station.
Already the English artillery from the hills beyond the town had begun shelling the town. Seeing a train ready, they tried to cut the railway line and destroy a bridge. The train got through just in time. It was the last train out of Pretoria and it was carrying the cash and assets down to the President at Machadodorp.
Once more Roberts was forced to halt and refit. He had pushed his troops so hard that many of the men had fallen sick; all needed rest; the horses were skeletons and unfit to march; his supplies and ammunition were running short.
As he waited, the Dutch began to recover heart. Botha had his main force some fifteen miles to the east across the Delagoa Railway, at Diamond Hill, but he himself toured up and down, inspiring the burghers with fresh spirit. De la Rey began raiding from the west. The English communications with Cape Town were a thousand miles of railway, and very vulnerable to attack. The Free State leaders de Wet and Prinsloo threatened to cut it in a dozen places.
Roberts drove Botha at once off Diamond Hill and made him retire away back a hundred miles to a position close in front of Machadodorp. He pushed cavalry after de la Rey until he forced his bands to break up into small pieces and to get away from Pretoria. He turned on de Wet and Prinsloo, and closed them in a net of troops: de Wet dashed out with a thousand men and got away; Prinsloo and the rest surrendered.
By the end of August Roberts was ready. His army was refitted and rested. Buller had advanced up on his right flank and cleared Natal and joined with him. De Wet and de la Rey were temporarily helpless.
He attacked straight down the railway at Botha, outflanked and chased him out of his position, broke up his army, and forced him with a few remnants to run for the inaccessible country to the north round Lydenburg. Kruger made across the Portuguese frontier, was interned and sent to Europe, and passed out of the active part of the history of South Africa. The Transvaal regular army had ceased to exist. The Transvaal Government was at an end, and the Transvaal was formally annexed by England. All that remained for the English was to clear up the country.