So you're curious. You want to hear the rest of it. And you're sure it's not just out of sympathy. Well, all right. There's a bar in the next block where we can get a booth and a couple of beers.
Now look, I don't need to be led! You don't need eyes to find your way to a bar on a hot summer day like this. It's toward the end of the block, just a few steps further.... Right here. There's a booth in the back where nobody will bother us for a while.
Okay, make mine the same and here's half a dollar to pay for them. Don't worry, I've got money enough to keep me in beer and pretzels for a long time. Nobody could accuse the professor of being stingy with the university funds when he paid me off.
It began about six months ago. I was in my third year at college, studying physics under Professor Martin. Maybe you've seen Martin around the campus—a rather thin guy with a face like the Rock of Gibraltar. One of the few profs who can still sound enthusiastic about their subject after twenty years of teaching it.
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?"