Julius Lothar Meyer independently developed a periodic table of the elements based on the periodicity of atomic properties. His 1870 table includes an atomic-volume curve that demonstrates periodicity with graphic clarity superior to Mendeleev's. The work was submitted for publication in 1868 — a year before Mendeleev — but published in 1870 due to editorial delays. Mendeleev added the predictive capacity for undiscovered elements, which cemented his historical priority.