About ten days before the surrender of the town, the scheme of the "Destroyers" was unwittingly disclosed through the foolishness of the man who had been apparently chosen to carry it out. Judge Kock, who was a friend of Dr. Krause's, came over to Johannesburg for the purpose of making a last and determined effort to destroy the mines. Being a great friend of the Krauses, he was invited to stay at their house. In a burst of confidence he produced a letter signed by a very high-placed official of the Executive Council, whereby he was empowered, in indefinite terms, to call for the co-operation of any military official whom he pleased. He showed Dr. Krause this letter and requested him to instruct the mine police and certain other mine officials to assist him. He was met with a blank refusal, and a threat that if he persisted in this undertaking he would be arrested. Judge Kock, or, as he then styled himself, "General" Kock, had gathered together a cosmopolitan force of about 100 men. About this time events were rapidly changing. The determined advance of the British forces and the panic-stricken retreat of the Boers had the effect of encouraging "General" Kock and his men. Dr. Krause's hands were full in attending to the military necessities of the situation. Urgent messages from Botha and the President were hourly passing over the wires. General French, who was advancing on Johannesburg from the east, had pressed forward to such an extent that the Boers retreating from Vereeniging were practically hemmed in by the British columns. Commandant Krause on the Sunday afternoon hastily gathered as many fighting men as he could muster, and with them occupied the hills surrounding Van Wyk's Rust, in order to check the advance of French and give the Boers an opportunity of retreating safely. On the Monday, while fighting was going on, he was obliged to leave his men--who by that time had been reinforced by the retreating Boers--for Johannesburg, on receiving an urgent message that chaos was reigning in town, and that the goods sheds at the station, where Government provisions and food-stuffs were stored, were being looted. On his return order was speedily restored. Tuesday, May 29th, was the eventful day in the history of the saving of the mines, as on this date Dr. Krause personally arrested "General" Kock and dispersed his band of followers. It happened in this way.