May 31, 2010 #1 Robertmet Materials Aug 5, 2007 153 http://www.dailymail.co.uk/news/wor...ret-Great-Wall-Chinas-strength-longevity.htmlHere's an interesting find .Like the pumice addition by the ancient Romans the old ways have their benefits !
http://www.dailymail.co.uk/news/wor...ret-Great-Wall-Chinas-strength-longevity.htmlHere's an interesting find .Like the pumice addition by the ancient Romans the old ways have their benefits !
