tag:blogger.com,1999:blog-2559120712893478325.post7975801983425707061..comments2024-03-22T10:16:40.966-04:00Comments on A Second Look: Going to the game?John D. Linnhttp://www.blogger.com/profile/14363389317652839129noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-2559120712893478325.post-88309636874923547342016-11-05T11:10:36.863-04:002016-11-05T11:10:36.863-04:00The Romans invented a super concrete much harder a...The Romans invented a super concrete much harder and more stable than ordinary cement. That is why the Colosseum and other structures have survived as long as they have. Part of that secret ingredient is volcanic ash which provides a crystal structure to resist cracking. Only in the last few decades have we also been able to produce super concrete. Impressive photos. Taken For Grantedhttps://www.blogger.com/profile/06763027485732267570noreply@blogger.com