Humm never underestamate primative man, or the power of oral traditions..comunications from one life time to the next has been happening from the point we started comunicating...waht d oyou think the cave paintings are? Also note that there have been mechanical motors before (greeks in alaxandra had devloped a stam engin but where sacked before they could exploit it), batteries existed in babalon (no idea on what they where used for yet but they had chmical bateries.) and before the age of exploration there was no need for acurate time keeping (anyone remember when the chinese devloped the water clock?). Never get to full of our advanced tech or underestamate primitive man..we have made some advances this is ture but every step is bulit on the previous step.