"If I had only known," he said, with a dreary shake of his snow-white head. "But," he added with a shrug, "I did not know. I was blinded by success, and a passionate devotion to my work." He drew a deep breath. "But I knew later. Oh, yes. I knew. The greatest triumph and the greatest disaster of my life was when I converted the paltry little coast defence submarines into the ocean-going pirates they afterwards became. But it was not until Germany declared a submarine blockade of these shores that I knew what I had done. Up to that time I had been a--German patriot. From that moment I became a simple, heart-broken human being. My legitimate engines of war had been turned against the innocent lives of a defenceless people, and when the massacre of fifteen hundred souls took place with the sinking of the _Lusitania_ I think for the time I became demented." He was breathing hard. His face had become almost stony in its expression. It was the face of a man who for the time is beyond all further feeling. Quite abruptly, however, he released his hold upon his foot, and ran his long fingers through his shock of white hair. "Ach! How willingly would I have undone all I had done. I tried to resign on various pleas. Health!" He laughed, a hollow, mocking laugh. "As well try to struggle free from the strangling rope of the hangman with hands tied. To my horror I found that I belonged body and soul to Germany, and my rank and wealth was the price the country had paid for my brains. Oh, yes, I was no honored patriot serving my country. I was its bond slave, the slave of Prussian militarism. And to the end of my days that slave I must remain. "Need I tell you of all the suffering I have since endured? No, I think not. No repentant murderer could have suffered more for his crimes than I have done. I have striven, by every possible argument, to assure myself that mine was not the blame, but no conviction has resulted. The world cannot blame more cruelly than I do myself, and yet--I am innocent of all intent. "Throughout all the struggle I have had with my own soul no glimmer of light reached me until my daughter came to my rescue. And I think it was her woman's wit, supported by her own brave heart, which has saved me. She, in her great pity and love of humanity, started a fresh thought in the poor brain with which Providence endowed me. It surely was only a woman's mind could have conceived so simple a solution to my trouble. It was all done in one brief sentence. She said, 'The brain that can invent to destroy can invent to save.' And from that moment hope came to me." He leant forward urgently. The veins at his temples stood out with the mental effort of the moment.