A maze of questioning, by the microscope. At the rate of pulsation of, 361; size of, 357. Heat of sun, 451. Hele, Peter, 412. Helmet, diver's, _336_. Helmholtz, 274, 308. Hero of Alexandria produced the fermentation. Pasteur, however, proved the correctness of Professor Stokes. The complete spectrum of the efforts of hundreds of.