There are thousands of periodic tables in web space, but this is the only comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Dr Mark R Leach.
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"Model demonstrating the telluric screw periodic system of Alexander-Emile Beguyer de Chancourtois proposed in a paper published in 1862.
"This model, made by the Science Museum in 1925, provides a rare physical realisation of arguably the earliest periodic system of for the elements. It was devised by the French geologist, Alexander-Emile Beguyer de Chancourtois in 1862, 7 years prior to Dmitri Mendeleev's periodic table.
"De Chancourtois arranged the elements in the order of their atomic weights along a helix which was traced on the surface of a vertical cylinder, with an angle of 45 degrees to its axis. The base of the cylinder was divided into 16 equal parts (the atomic weight of oxygen), and the lengths of the spiral corresponding to the weights of the elements were found by taking the one-sixteenth part of a complete turn as a unit":