Dmitri Mendeleev
Unaware of the earlier work on periodic tables going on in the 1860s, he made the following table:
By adding additional elements following this pattern, Mendeleev developed his extended version of the periodic table. On 6 March 1869, he made a formal presentation to the Russian Chemical Society, titled "The Dependence between the Properties of the Atomic Weights of the Elements", which described elements according to both atomic weight (now called "relative atomic mass") and valence. This presentation stated that
C. H. D. Buys Ballot
Buys Ballot devised a tabular method for investigating periodicity in time series. In 1847 he used the table now named after him to determine the period of the sun's rotation from daily observations of temperature in the Netherlands from 1729 to 1846.