Crookes' spiral, 1888.
© Science Museum / Science & Society Picture Library
This spiral representing the order of evolution of the elements, was made by Sir William Crookes (1832-1919). In 1886 Crookes described, in an addres to the British Asociation, an improved diagrammatic method of illustrating the periodic table. The table showed the chemical relationships between the elements and also indicated the order of their evolution from what he believed to be primal (protyle) matter. He modified his zig-zag table to this model, later adding the elements discovered by William Ramsay, the noble, or inert, gases.