Let us suppose for a moment, however, that the incidents in the Levelland epidemic might have occurred just as they are described by the NICAP committee. If UFOs had been visiting the earth that week, projecting a force field that performed as claimed, certain other events should also have occurred. Thousands of automobiles should have been, but were not, temporarily disabled in the neighborhood of every car-stopping UFO. Fantastic traffic jams have sometimes been caused by torrid weather and consequent vapor locks in the fuel lines of automobile engines. In June 1961, for example, a sudden heat wave in Boston caused a vapor-lock epidemic that tied up traffic on the main highways for three hours. On some stretches of road so many cars were immobilized that, with their hoods up to cool off, they looked “like a convention of pelicans.” No such traffic jams were reported in connection with the 1957 UFOs. In South Springfield, Ohio, a car and a taxicab stalled but the vehicles around them experienced no trouble. One car stalled in Houston and another in Santa Fe, but the traffic around them proceeded as usual. Hundreds of TV sets should have blurred, but did not, in the neighborhood of every TV-blurring UFO. Equally surprising, no one complained of UFO interference with hi-fi sets, vacuum cleaners, refrigerators, washing machines, irons, freezers, or electric razors. No airplane, helicopter, motorcycle, or ocean liner reported engine trouble. At least two landings were reported, in New Mexico and Ohio. No physical evidence of landing could be found--shrubs were not crushed, grass was not scorched, ground was not disturbed. Except for the _Sebago_, no radar reported the presence of a UFO. Moonwatch teams, trained specifically to detect, observe, and plot the exact path of moving objects in the sky, were on the alert that week all over the United States and Canada. They did not see even one unidentified flying object. _“G-Fields” and UFO Propulsion_ Even more fantastic than the E-M force that stops cars and silences radios is the artificial gravitational field or “G-field,” which saucer enthusiasts call on to account for all UFOs whose reported behavior clearly contradicts the laws of physics. Employing electromagnetic forces, the UFOs supposedly can create a variety of G-fields as needed, to be used as a defense weapon, a means to invisibility, or a method of propulsion[IX-18, IX-19]. Writers of science fiction have regularly utilized similar handy expedients such as “gravity shields,” “force fields,” “inertia drives,” and “space warps” to move their heroes quickly from earth to remote parts of the galaxy. Physicists, too, dream of revealing new aspects of nature that would allow man to nullify the effects of gravity and make short cuts through space, but they realize that such devices, even if theoretically not impossible, must await unimaginable discoveries about nature and are at least far in the future.