Number 178 (Story #2), May 10, 1994 by Phillip F. Schewe and Ben Stein HALTING AND REVERSING THE DESTRUCTION OF OZONE in the stratoshpere is a problem of great importance: the less protective ozone there is, the more harmful ultraviolet radiation reaches the Earth. Alfred Wong of UCLA studies this problem using a 2.4-m ozone- filled chamber. When CFCl-3 molecules are introduced and when an artificial source of sunlight starts to liberate free chlorine, the density of ozone in the chamber begins to fall, mimicking the catalytic destruction of ozone in the atmosphere. Wong's effort to counteract this effect is to inject a current of negatively-charged oxygen atoms and molecules. These attach themselves to the chlorine atoms which can then be collected on a positively-charged surface. Thereafter the ambient uncharged oxygen can reform as ozone now that it is spared the destructive presence of chlorine. Wong believes that much more research is necessary before a field test of this method can be attempted. He points out that the charge-induced approach is quite different from proposed chemical means for the regeneration of ozone since the negative charges are all recovered, leaving behind no greenhouse-inducing substances. (A.Y. Wong et al., Phys. Rev. Lett., 9 May.)