That was done, now. After this last little rest he would go back to his laboratory in the _Himmlerstrasse_ and take the final step. So now he could let himself relax and feel the warmth of the sun. * * * * * Professor Kempfer smiled wearily at the sunshine. The good, constant sun, he thought, that gives of itself to all of us, no matter who or where we are. Spring ... April, 1958. Had it really been fifteen years--and sixteen years since the end of the war? It didn't seem possible. But then one day had been exactly like another for him, with only an electric light in the basement where his real apparatus was, an electric light that never told him whether it was morning, noon, or night. I have become a cave-dweller! he thought with sudden realization. I have forgotten to think in terms of serial time. What an odd little trick I have played on myself! Had he _really_ been coming here, to this bench, every clear day for _fifteen_ years? Impossible! But.... He counted on his fingers. 1940 was the year England had surrendered, with its air force destroyed and the Luftwaffe flying unchallenged air cover for the swift invasion. He had been sent to England late that year, to supervise the shipment home of the ultra-short wave-length radar from the Royal Navy's anti-submarine warfare school. And 1941 was the year the U-boats took firm control of the Atlantic. 1942 was the year the Russians lost at Stalingrad, starved by the millions, and surrendered to a Wehrmacht fed on shiploads of Argentinian beef. 1942 was the end of the war, yes. So it _had_ been that long. I have become an indrawn old man, he thought to himself in bemusement. So very busy with myself ... and the world has gone by, even while I sat here and might have watched it, if I'd taken the trouble. The world.... He took the sandwich from his coat pocket, unwrapped it, and began to eat. But after the first few bites he forgot it, and held it in one hand while he stared sightlessly in front of him. His pale, mobile lips fell into a wry smile. The world--the vigorous young world, so full of strength, so confident ... while I worked in my cellar like some Bolshevik dreaming of a fantastic bomb that would wipe out all my enemies at a stroke.