This digital collection features selected visual representations of the periodic table of the elements, with an emphasis on alternative layouts including circular, cylindrical, pyramidal, spiral, and triangular forms. Ranging in date from the 1860s to the 1990s, the materials provide a panorama of the historic evolution of the periodic table following Dmitri Mendeleev's initial 1869 design. Illustrations depicting chemical elements and concepts in atomic theory are also included in this collection.
