For example, the trucks which came to carry the Embassy shipment to the spaceport. They were perfectly ordinary trucks, hired in a perfectly ordinary way by the ambassador's secretary. They came trundling across the square and into the Embassy gate. The ostentatiously loafing plainclothesmen could look in and see the waiting parcels loaded on them. The first truckload was quite unsuspicious. There was no package in the lot which could have held a man in even the most impossibly cramped of positions. But the police took no chances. Ten blocks from the Embassy the cops stopped it and verified the licenses and identities of the driver and his helper. This was a moderately lengthy business. While it went on, plainclothesmen worked over the packages in the truck's body and put stethoscopes to any of more than one cubic foot capacity. They waved the truck on. Meanwhile the second truck was loading up. And the watching, ostensible loafers saw that nearly the last item to be put on it was a large box which hadn't been visible before. It was carried with some care, and it was marked fragile, and it was put into place and wedged fast with other parcels. The plainclothesmen looked at each other with anticipatory glee. One of them reported the last large box with almost lyric enthusiasm. When the second truck left the Embassy with the large box, a police truck came innocently out of nowhere and just happened to be going the same way. Ten blocks away, again the truck load of Embassy parcels was flagged down and its driver's license and identity was verified. A plainclothesman put a stethoscope on the questionable case. He beamed, and made a suitable signal. The truck went on, while zestful, Machiavelian plans took effect. Five blocks farther, an unmarked empty truck came hurtling out of a side street, sideswiped the truck from the Embassy, and went careening away down the street without stopping. The trailing police truck made no attempt at pursuit. Instead, it stopped helpfully by the truck which had been hit. A wheel was hopelessly gone. So uniformed police, with conspicuously happy expressions, cleared a space around the stalled truck and stood guard over the parcels under diplomatic seal. With eager helpfulness, they sent for other transportation for the Embassy's shipment. A sneeze was heard from within the mass of guarded freight, and the policemen shook hands with each other. When substitute trucks came--there were two of them--they loaded one high with Embassy parcels and sent it off to the spaceport with their blessing. There remained just one, single, large-sized box to be put on the second vehicle. They bumped it on the ground, and a startled grunt came from within.