Science: Rocketing

Two thousand excited Germans sat beside Berlin's famed Avis Speedway one day last week, and listened to a lecture on rockets. The lecturer was Fritz von Opel, motor magnate. Beside him stood a little racing car with two unusual accessories. In its rear it had something that looked like an exaggerated exhaust pipe. This, explained Herr von Opel, was a chamber for the explosion of rockets, the car's only means of locomotion. The other feature was a pair of little wings like an airplane's, except that their pitch was inverted. These, said Herr von...