Newlands

Somewhat later, about 1864, a chemist by the name of Newlands came up with what he called the law of octaves. This idea was a bit more developed than Döbereiner's triads. Newlands arranged the known elements by atomic weights. In doing so, he noticed some recurring patterns, and the patterns were such that if he broke up his list of elements into groups of seven (starting a new row with the eighth element), the first element in each of those groups were similar to one another. So was the second element in each group and the third and so on. There was a certain pattern in the properties of elements that became even more apparent as time went on. In the 1860s quite a bit of new information developed. In no small part this was due to the ideas of Avogadro begin championed by Stanislao Cannizarro at the First International Chemical Congress in Karlsruhe, Germany in 1860.
Newlands' Octaves
H Li Ga B C N O
F Na Mg Al Si P S
Cl K Ca Cr Ti Mn Fe
Co,Ni Cu Zn Y In As Se
Br Rb Sr Ce,La Zr Di,Mo Ro,Ru
Pd Ag Cd U Sn Sb Te
I Cs Ba,V Ta W Nb Au
Pt,Ir Tl Pb Th Hg Bi Cs
Adapted from Isaac Asimov's "A Short History of Chemistry," Doubleday & Company, Garden City, NY, 1965.