He possessed a vast knowledge of medicinal herbs, but he had no conception of chemistry. He extracted curative salts and drugs from earths and minerals, but he could not explain their nature, was entirely ignorant of the difference between acids and alkalis, and he knew nothing of the laws and theories of chemical reactions. He had discovered that the radioactive mineral, in combination with certain ores, emitted a brilliant, apparently perpetual light, but he was unaware that the light was the result of the decomposition of the metallic element, radium. And his most uncanny and seemingly supernatural power, that of appearing to fade and float through the air, was utterly inexplicable, he admitted. It was a trick or a power which, he claimed, had been inherited for countless generations by his clan; it was, so he declared, purely mental and not mechanical nor chemical, and though possibly--for I am broad-minded enough to admit there are more things in heaven and on earth than any scientist has dreamed of in his philosophy--it may have been the Indian Yogi’s alleged power to transport themselves bodily for any distance, yet I believed and still believe it to be some form of hypnotism. He admitted that he could not perform the seeming miracle, except under certain conditions and in certain environments, and I mentally classed it with the rope-climbing, dismembering and mango-growing tricks of the Hindoo fakirs. But regardless of all this, in spite of the fact that the old sorcerer was, scientifically speaking, as ignorant as any of his people, still he was a veritable storehouse of the history, the traditions, the legends and the records of his race. That he was extremely old was certain. That he had discovered the elixir of perpetual youth, as he claimed, seemed quite possible and even probable, when I looked upon his youthful face, his active muscular body and his snow-white hair. That he had always looked exactly the same, from the time of the earliest recollections of the oldest inhabitants of Mictolan, all agreed, and all declared also, that he had been the same in the days of their fathers and their fathers’ fathers _ad infinitum_. But I knew, from long experience, how difficult, almost impossible, it is to disentangle fact and fiction in Indian traditions and memories, and whether he was a century or ten centuries of age, I could not hazard a guess. * * * * *