The unit we were studying at the time was the one on light and physical optics, primarily a study of the spectrum stretching from x-rays beyond the ultra-violet to the visible spectrum, down to the infra-red and radio waves and the short waves used in television and radar. I had been absent from class a week and on my return the professor invited me to dinner. After the dishes had been cleared away he leaned back in his chair and lit what I took to be his usual after dinner cigar. "I like to meet my students informally, Charles," he began. "Sorry that your wife couldn't come but I understand she's ... well...." He let the sentence trail off. I sat there feeling rather sick. It's one of those things you hope everybody has heard about so you don't have to explain, to sit and take their looks of pity and sympathy. Apparently the professor hadn't heard. "I'm sorry," I said. "I thought you knew. Both Alice and the baby died." The hand he held his cigar in quivered a little. "I'm sorry," he said, and mercifully dropped it there. Then he changed the subject to the one he had in mind when he had asked me to dinner. "Light, Charles, is such a large subject--and, comparatively speaking, so little is known about it. But perhaps--perhaps I know more than most. And if you wish, you can too. Would you like to see the world you live in, Charles? Not just the one tenth of one percent that they call the visible spectrum, but all of it, the whole glorious universe of light?" He took me into his confidence on his favorite research project, an attempt to see wavelengths other than those in the visible spectrum. His enthusiasm was catching and there wasn't much hesitation. I signed the paper releasing the university from all responsibility in case of an "accident." So easy to sign one's life away--though it wasn't actually my life, only my eyesight. * * * * * The treatments began immediately. First, adaptation of vision to a dark room, like those used for flyers during the war. Then the drops of black liquid that the professor had invented, slowly spreading over the eyes, subtly altering the rods and cones of the retina, the nerve endings sensitive to light. And I began to live in a gradually fading world. Have you ever wondered what it's like to go blind? The increasing dusk and darkness around the edges of your vision, the little errors and mistakes that begin to crop up in everyday life. Your blunder over a stool that you didn't quite see, your snubbing someone on the street whom you didn't recognize in time, the gradual awareness among your friends that something was wrong with your eyes and their crude attempts to make it "easier" for you.