Note 17 — Chapter I · PREAMBLE: ON THE ORIGIN OF WEAPONS.
Reading edition
M. Eduard Pietri distributes Prehistoric Archæology proper into two ages, the Agreutic and the Georgic. Under the former he classifies the Barylithic (glacial Drift age) and the Leptolithic. Under the Georgic are included the Neolithic, the Chalcitic (copper and bronze), and the Proto-sideric.