Technological upheavals caused by inventions of our own are bad enough, but this was the ultimate depression, caused by the ultimate alien invention—which no Earthman ever saw! The Ambassador from Outer Space sprang to his feet, taking Jerry's extended hand in a firm, warm grasp. Jerry had been prepared for almost anything—a scholarly brontosaurus, perhaps, or an educated squid or giant caterpillar with telepathic powers. But the Ambassador didn't even have antennae, gills, or green hair. He was