The development of the periodic table began in the 1800s as chemists started to recognize similarities in the properties of various elements and place them into familes. Döbereiner started with a few family groups each containing three elements. Newlands put the elements of those familes in repeating groups called octaves (as with musical notes). Meyer noted additional repating properties. Mendeleev put it all together into what has become the periodic table of the elements. The pages in this section give you some information about what they did.