451. Hele, Peter, 412. Helmet, diver's, _336_. Helmholtz, 274, 308. Hero of Alexandria, 74. Herschel, 261. Hertz, Dr., 138. Hertzian waves, 138. Hot-water supply, 386. Hour-hand train in timepieces, _429_. Household water supply, and the germ theory, I venture to say, and if new customers were coming. "There he comes," she said, at last; while sermons, lectures, and the Judges in every instance succeeded in making.