Nathan B 6 By bakernw 400 BCE democritus Democritus is known for the theory that everything is made of atoms. Atoms are invisible. 348 BCE plato 1400 aristotle 1778 lavoisier 1869 dmitri mendeleev 1887 photoelectric effect 1897 jj thompson 1899 ernest rutherford 1903 the curies 1903 john dalton 1905 plancks quantum theory of light 1913 Neils bohr 1914 henry gj mosely 1916 Albert Einstein 1923 robert millikan 1925 werner heisenberg 1926 schrodinger equation 1927 robert boyle 1932 james chadwick 1988 The Alchemist