He suggested then that I could study at Cambridge under Lord Rayleigh, who had succeeded Maxwell as professor of physics. I declined the suggestion on the ground that I had never heard of Lord Rayleigh before. Niven laughed again, even more heartily than before, and assured me that Lord Rayleigh was a great physicist in spite of the fact that his great fame had never reached my ears. An English lord a great physicist! The idea struck me as strange, but Niven looked so friendly and so sincere that I could not help believing that he really meant what he said. He invited me to lunch, and before we parted I assured him that I would come back to Cambridge in the following October and place myself under his guidance. This conference with Niven sobered me up very considerably; it convinced me that my great aspiration and my small preparation in physics were far from being of the same order of magnitude. I confessed to Niven that my success in winning prizes in science at Columbia College had led to my belief that I knew more physics than I really did. “Confession is a splendid thing for the soul,” said Niven, and added: “But do not permit that anything I have said dampen your courage. A physicist needs courage, and few mortals were braver than Maxwell. The world knows only a little of his great electrical theory, but it knows even less of his great moral courage.” He gave me a copy of Campbell’s life of Maxwell; I read it from cover to cover before I left London, and it contributed much to the learning which I had promised to bring to Idvor. It certainly convinced me that Maxwell had a vastly better knowledge of physics when he graduated at Cambridge than I had picked up at Columbia. That gave me much healthy food for serious thought. A straight line from London to Idvor passes through Switzerland, and I proposed to follow that line in my journey as closely as practicable. My ticket took me from London to Lucerne directly; the journey from Lucerne to Idvor I left undetermined until I reached Lucerne. I had no time nor inclination to explore the wonders of London, Paris, or of any other great place in Europe before I had seen Idvor again. Mother, Idvor, and Maxwell’s new electrical theory had brought me to Europe, and I wished to see them as soon as possible, and in the order named; everything else could wait. Besides, I sincerely believed that these places had little to offer to a fellow like me, who knew the great things of New York. I was much disposed to look down upon things in Europe, a mental attitude which is not uncommon among American immigrants when they go back to pay a temporary visit to Europe. I had it quite strongly, but sobering experiences like the conference with Niven in Cambridge helped me to apply suitable correction factors to this mental attitude. The following brief description of one of these experiences bears upon this point. * * * * *