336 BIOLOGY FOR BEGINNERS 



his simple crops, community life and society had their earliest 

 beginnings. 



Man's development is usually classified by the implements he 

 had learned to use. 



1. Primitive Man. Without weapons, tools, or fire. 



2. Old Stone Age. Stone weapons and tools, probably used fire. 



Contemporary with mammoth and cave 

 bear. 



FIG. 110. Skull cap of Pithecanthropus erectus, the 

 fossil man-like ape of Java. Shown from above and 

 in profile; from Wei tall u. Menschheit, see Kellogg. 



3. New Stone Age. Used polished stone implements. 



Perhaps made crude pottery. 



Erected stone monuments, buried the dead. 



A period of many wars and migrations. 



4. Age of Metals. 



(a) Copper and .gold first used because found pure in nature; 

 could be shaped by hammering and did not have to be 

 melted. 



(b) Bronze, an alloy of melted copper and tin which made ex- 



cellent implements and did not require great heat to melt. 



(c) Iron, required skillful smelting and tempering, needing much 



higher temperature. Best metal for all uses. Brings 

 us down to modern times. 



