Dielectric breakdown

The theories proposed for the breakdown of solids (outlined in last year´s review) give general order-of-magnitude agreement with the experimental values available. But in order to go more closely into the process and make finer distinctions, data for a wide range of conditions are needed. Three papers have appeared this year which represent steps in this direction: K. W. Plessner on thin films, K. J. Keller on the temperature dependence of dielectric strength and J. W. Davisson on the temperature dependence of the direction of breakdown paths.