> Concrete has been known since antiquity, but steel-reinforced concrete and massive numerical calculations of stress-distribution, is the tools that makes the

> Concrete has been known since antiquity, but steel-reinforced concrete and massive numerical calculations of stress-distribution, is the tools that makes the difference between using concrete as a filler material between stones, and as gravity-defying curved but perfectly safe load-bearing wall. Ahem. http://www.google.ie/imgres?imgurl=http://romanconcrete.com/graphics/pantheon_dome.jpg&imgrefurl=http://romanconcrete.com/about.htm&h=900&w=600&sz=91&tbnid=XqbRatDd5am7uM:&tbnh=90&tbnw=60&prev=/search%3Fq%3Dpantheon%2Bdome%26tbm%3Disch%26tbo%3Du&zoom=1&q=pantheon+dome&docid=0KpRyueAMS9WzM&sa=X&ei=_4TxTq2nF5SyhAfK-N2zAQ&ved=0CD0Q9QEwAw&dur=2401 http://www.google.ie/imgres?imgurl=http://romanconcrete.com/...