The nucleus is very small compared to the atom as a whole: as electrons are even smaller, most of an atom is empty space the diameter of a nucleus can be 100,000 times less than the diameter of an ...

(London and Toronto: Hodder and Stoughton, Ltd., 1923.) 2s. 6d. net. (2) The Atom and the Bohr Theory of its Structure: an Elementary Presentation. By H. A. Kramers Helge Holst. Translated from ...