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is divided as to periods : 1. Archaeolithic [Gr.], = that of the Tertiary (Mortillet) ; with a problematic variety of stone implement fashioned by fire and breakage rougher than the chipping which characterizes the age.

is divided as to periods : 2. Palaeolithic, - that of the Drift ; age of chipped tools, with the mammoth, cave-bear, woolly haired rhinoceros.

is divided as to periods : 3. Neolithic, = later Stone age, of ground and polished weapons and instruments, gold ornaments.

is divided as to periods : 4. Bronze age, = of bronze used for arms and all cutting instruments.

is divided as to periods : 5. Iron age, = of iron instead of bronze for arms, knives, and bronze for ornament only. But the ages of stone, of bronze, and of iron were, in different laces, coexistent. Indeed, in some countries the stone age still continues, the people being unacquainted with the use of metal. (See Lubbock, Pre-historic Archeology. )