Scientific Revolution

Still it is very quiet in this group. Nevertheless some people are visiting

here. There were several reactions on my previous message. I will try to 
start some more discussion by proposing subjects.
My first question is:
Why started the Scientific Revolution only in the sixtienth century and
not 
long before?
I know there is writen a lot about this subject but I still don't
understand 
why people before that time didn't think about performing experiments and 
found such simple laws we now all learn at school. For example even the 
Egyptians used a lever to move heavy stones, but why was it not early than

Galileo that someone did experiments to try to make a theory?
I hope for a vividly discussion.