By the end of 1860 around 60 elements had been discovered on the periodic table
Dmitri Mendeleev produced a table based on atomic weights but arranged 'periodically' with elements with similar properties under each other. His Periodic Table included the 66 known elements organized by atomic weights.
William Ramsay discovered the Noble Gases.
John Newlands arranged the known elements in order of atomic weights & observed similarities between some elements
Johann Dobereiner developed groups of 3 elements with similar properties