i. Mendeleev found that the chemical and physical properties of elements showed repetition after certain intervals.
ii. He arranged all the known elements in a tabular form in the increasing order of their atomic masses in horizontal rows till he encountered an element which had properties similar to the first element.
iii. He placed this element below the first element and thus started the second row of elements.
iv. Proceeding in this manner he could arrange all the 63 elements known till then according to their properties and thus created the first periodic table.
