http://www.google.com/search?q=history+of+engraving+techniques&hl=en&safe=active&tbs=tl:1&tbo=u&ei=4-dVS_L2CoroM-TehZgJ&sa=X&oi=timeline_result&ct=title&resnum=11&ved=0CC8Q5wIwCg http://www.metmuseum.org/toah/hd/engr/hd_engr.htm#slideshow1...
