Ernest Rutherford on Electron

“The theory that the atoms of matter are all built up of some simple fundamental unit or protyle has been advanced at various times by prominent chemists and physicists. One of the earliest hypotheses of this kind was that due to Prout, who supposed that all the elements were built up of hydrogen. This general point of view has received strong support from observations that the properties of elements vary in a periodic manner with their atomic weight. This is exemplified by the classification of the elements according to the well-known periodic law. In order to explain the electrical and optical properties of matter, it was generally supposed that the atom consisted of a number of positively and negatively charged particles, held in equilibrium by electrical forces. The properties of such electrical atoms were early studied by Larmor and Lorentz.”

“The first point that arises is the atom. I was brought up to look at the atom as a nice hard fellow, red or grey in colour, according to taste. In order to explain the facts, however, the atom cannot be regarded as a sphere of material, but rather as a sort of wave motion of a peculiar kind. The theory of wave-mechanics, however bizarre it may appear... has the astonishing virtue that it works, and works in detail, so that it is now possible to understand and explain things which looked almost impossible in earlier days. One of the problems encountered is the relation between the electron, an atom and the radiation produced by them jointly; the new mechanics states the type of radiation emitted with correct numerical relations. When applied to the periodic table, a competent and laborious mathematician can predict the periodic law from first principles.”