Ulric cared little at that moment whether his order were obeyed or not. He had forced a passage for himself through to the terrace, and stood confronting the master with all the defiant hostility of his rebellious nature, his gigantic form towering nearly a head above his fellows. He was a born leader of the masses; his fierce energy and despotic will carried them with him in blind obedience, and, spite of all that had happened, that might happen yet, his command over them was still for the time being unlimited. All the advantage which Arthur had obtained was called into question, if not wholly destroyed, by the mere appearance on the scene of this man whose influence worked at least as powerfully as his own.
"Where are our mates?" asked Hartmann in a tone of menace, and stepping up still closer. "We want them out at once! We will have no violence used to any of us."
"And I will not have my machinery destroyed," answered Arthur coldly and calmly. "I had the men arrested, though they were only the tools in another's hand. Who ordered that attempt upon the engines?"
There was a triumphant gleam in Ulric's eye; he had foreseen this firmness and built his plan upon it. He himself needed no pretext; he was bent on satisfying his hatred at any cost, but his partisans, wavering and ready to desert their flag, were in want of some provocation to urge them forward; it was necessary now to goad them on, and the adversary was bold and proud enough to offer them an incentive.
"I owe you no answers," he said disdainfully, "and I shall not allow myself to be questioned in that dictatorial way. Give up the prisoners, all the men on the works demand it, or" .... and his look completed the threat.
"The prisoners will be detained," declared Arthur unmoved, "and you, Hartmann, have no longer the right to speak in the name of all the men employed on the works; half of them have seceded from you already. I have nothing more to say to you."
"But I have something to say to you," shouted Ulric, desperate with rage. "Forwards," he cried, turning to the rebel masses, "forwards, on to our mates, strike down all that comes in your way!"
He would have rushed upon Berkow, thereby giving the signal for a general onset, but, before he could do so, before it could be determined whether the crowd behind him would render or refuse obedience, there boomed suddenly through the air a strange and terrible sound, making all the ground around them tremble.
The leader stopped electrified, and all present stood spell-bound, listening breathlessly for what would follow. It had been like the reverberation of a dull and distant shock, coming, as it seemed, from the very bowels of the earth, and was succeeded by a low rumble under ground which lasted a few seconds; then all was still as death, and hundreds of scared faces were turned in the direction of the works.
"Good God! that came from the mine; something has happened there!" cried Lawrence, with a great start of alarm.