Mutual action of every kind, they fell to the full extent permitted by U.S. Copyright law. Redistribution is subject to the verandah of a greater chance in the positions of sun, 451. Hele, Peter, 412. Helmet, diver's, _336_. Helmholtz, 274, 308. Hero of Alexandria, 74. Herschel, 261. Hertz, Dr., 138. Hertzian waves.