In 1869,     Russian chemist Dmitri Ivanovich Mendeleyev arranged 63 elements by increasing mass in several columns, noting recurring chemical properties. It's sometimes said that he played "chemical solitaire" on long train journeys, using cards with the symbols and, therefore, the atomic weights of the known elements. Another possibility is that he was partially inspired by the Sanskrit alphabet's periodicity, which was acknowledged to him by his friend and linguist Otto von Böhtlingk. Mendeleev used the trends he saw to suggest that atomic weights of some elements were incorrect and accordingly changed their placements: for example, he figured there was no place for trivalent beryllium with the mass of 14 in his work, and he cut both the relative atomic mass and valency of beryllium by a 3rd, suggesting it was a divalent element with the mass of 9.4. Mendeleev widely printed broadsheets of the table to varied chemists in Russia and abroad. Mendeleev argued in 1869, that there have been seven styles of highest oxides. Mendeleev continued to boost his ordering; in 1870, it gained a tabular shape, and every column was given its own highest oxide; in 1871, he further developed it and formulated what he termed the "law of periodicity." Some changes also occurred with new revisions, with some elements changing positions.

~Manit, Vivaan, Devraj, Aarav, Soha