"Gas lights," supplied Helen, "if Spencer Tracy--I mean Thomas Edison--hadn't been fired from his job as candy-butcher on the railroad." "America a French colony," I suggested, "if Napoleon hadn't been defeated at Waterloo. He had designs on us, you know. That's why he placed Maximilian in Mexico--" "A powerful priesthood governing the world," broke in Helen again. "Would that be the Papal State? Or could it have been--Atlantis? If that island had not sunk?" "That there 'C.S.A.' had me stumped f'r a minute," said Hank, "but I got it now. That stands f'r the 'Confederate States of America!' If Pickett had come up at Gettysburg!" "But that other world of 'might-have-been'?" I demanded eagerly. "The most awe-inspiring one we saw? The one where giant spacecraft lay in their cradles? What could that have sprung from?" There was silence for a moment. Then Hank queried, "Did either o' you happen to notice the name o' that port?" Helen said, "I--I'm not exactly sure, but I thought it was the daVinci Spaceport--" "That's whut I thought, too," said Hank. "I reckon there's your answer, Jim. Back there in the Middle Ages, one day old Leonardo musa blew his nose or stubbed his toe or done somethin' he didn't do in _our_ hist'ry--an' as a result, he succeeded in doin' whut he never done in our time, though he spent half his life atryin' to. He invented aircraft. "Which give man a flyin' start o' four hundred years or so over where he is in our universe. So that in the mebbe world which sprung from daVinci's accident, man has learned how to navee-gate space." * * * * * Well, that was all very well. I suppose I was getting an education in cockeyed history that Beard or Gibbon or any tome-pedant would have swapped his eyeteeth for. But I'm not the kind of guy who exists on brain-food alone. I've got a hollow, pear-shaped bulb a few inches south of my diaphragm, and regularly, about six times a day, this aforesaid vacancy declares itself ready, willing and able to take care of a few pecks of assorted groceries. A mild attack of looseness around the belt reminded me that this was one of those times. I said, "Talking about space, Hank, that's what I've got the most of in my stomach. What say we tool this period-perambulating push-cart up to an 'ought-to-have-been' café and give the inner man something to think about?" Helen nodded approval to my idea. "I could use a little food myself, Hank." Hank wet his lips. "J-jim--" he faltered. "Now, look, pal," I declared firmly, "I know you're having a good time. This sort of thing is right up your pet alley. But have a little consideration for your passengers. All Helen and I want is victuals, and we'll travel with you from here to the universe where Adam didn't eat the apple--right, Helen? A round trip for a square meal; that's a fair exchange, isn't it?" * * * * *