Julius Lothar Meyer
In 1869, Dmitri Mendeleev published a periodic table of all known elements (he predicted several new elements to complete the table, and corrected some atomic weights). A few months later, Meyer published a revised and expanded version of his 1864 table independently, which was similar to that published by Mendeleev (Meyer had been sent a copy of Mendeleev's table earlier; Mendeleev had sent it to many well-known chemists of his day) and a paper showing graphically the periodicity of the elements as a function of atomic weight. Meyer, as well as other chemists, was doubtful about Mendeleev's periodic law, and he criticized Mendeleev for "changing existing elements' atomic weights, only regarding possibility of periodical law in its structure". However, Mendeleev's work received significant support, when the new elements were found as predicted and atomic weights accordingly.
Geologic time scale
British geologists were also responsible for the grouping of periods into eras and the subdivision of the Tertiary and Quaternary periods into epochs. In 1841 John Phillips published the first global geologic time scale based on the types of fossils found in each era. Phillips' scale helped standardize the use of terms like "Paleozoic" ("old life") which he extended to cover a larger period than it had in previous usage, and "Mesozoic" ("middle life") which he invented.