one month of hell

05:48 pm - some interesting links, possibly relevant

the history of zero

http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Zero.html

the history of glass

http://www.glassblowing.com/hotglass/history.php

the history of rubber

http://lala.essortment.com/historyofrubbe_rcml.htm

on water wells

http://en.wikipedia.org/wiki/Water_well