It's interesting how the ancients sometimes possessed superior knowledge compared to times that came afterwards.  There's an article at Nature.com which discusses how a strong steel material with carbon nanotube structure may have been developed as far back as the 900s in or around Damascus, though the knowledge appears to have been lost in the 1700s.  It's just a theory, but it wouldn't surprise me if it were proven that such technology were used for military advantage centuries ago.See: Sharpest cut from nanotube sword: Carbon nanotech may have given swords of Damascus their edge.

Archimedes alone is testament to this phenomenon.  There were great thinkers ahead of their time, but they were so secretive in their designs, when they died, their knowledge died with them.  Their unique skills were their livelihood and so they jealously guarded their secrets.