No scientific theory ever became accepted as fact so quickly as Friedmann's theory of the Xi effect, but then no other theory before ever had such a convincing array of scientific evidence to support it. The change in the tint of the landscape that Arnold had foreseen eventually developed but for several weeks it was too slight to be readily obvious. The effect was the same as if everyone had gone color-blind to an effective wave length of about 6500A. It was disconcerting to find that your hedge of geraniums was black instead of scarlet, and the absence of stop-lights was nearly disastrous. Some women became violently hysterical when they first beheld the inky fluid oozing from their veins. But after the novelty had worn off the public soon lost interest. They had lived through the invasion from Mars, the flying saucers, and other scientific gags, and doubtless in time this, too, would pass. Besides, how could you expect people to work up any enthusiasm over something when they weren't even sure how to pronounce it?
But as orange and yellow followed red into the gray there came a change in the public attitude, a kind of half-credulous belief mingled with misgiving and dismay. Men still laughed, and joked about the Xi effect over their old-fashioneds at the country club, but just when everybody was