Dimitri Mendeleev [local] is the Russian chemist who is considered the father of the modern periodic table. Mendeleev published his Principles of Chemistry in 1869 which included a crude table [local] of then known 63 chemical elements. With his table, Mendeleev accurately predicted three yet-to-be-discovered elements including eka-silicon and eka-boron. Mendeleev's genius was in breaking from a strict mass order arrangement of the elements and leaving gaps for undiscovered elements.