Model demonstrating the telluric screw periodic system

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.