The millions of different substances that make up the world can be reduced to a comparatively small number of chemical elements. These, arranged in order of their atomic number, form the Periodic Table. This program from the BBC archives provides a comprehensive overview of the development of the table. It discusses the work of John Dalton, Johann Döbereiner, and John Newland, and the creation of the first table by Dmitri Mendeleyev in the late 19th century. Later refinements by Henry Moseley, and the 1950s discovery of the artificial element #93 by Edwin MacMillan, are also discussed. The evolution of the table over the past two centuries is clearly and cleverly illustrated through computer animation and song. A BBC Production. (21 minutes)