1 result for (book:tps2 AND session:604 AND stemmed:subject)
[... 80 paragraphs ...]
This is a difficult subject. For the movement of heavy tons of rock for example different techniques, using sound and precise mathematical calculations were necessary. Many civilizations grew and flourished in fertile areas simply because the people knew how to make them fertile and to keep them that way.
[... 3 paragraphs ...]