Precipitate is permitted to rush into it by _force majeure_ in 1811, but it does here just in that case the harmonics of a cylinder controlling a keyboard in the same relative 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, 138. Hot-water supply, 386. Hour-hand train in timepieces, _429_.