Pseudo-Apuleius, Herbarium (about 600 AD, now in Leiden) Papyrus came first Scribes carved the first writing on wet clay tablets, but soon after that, about 3000 BC, the Egyptians invented papyrus. By about 500 [...]
A woman creates a pattern with colored sand for Diwali All over India, women use colored rice flour or wheat flour, or colored sand, to make patterns on the ground to celebrate holidays like Diwali. People [...]
Need chalk? Buy chalk Chalk has calcium in it Take a piece of regular white chalk, like for writing on a blackboard. Make sure the chalk is calcium carbonate like [...]
Chalk cliff (made of calcium atoms) in Cottonwood Canyon, Pueblo, Colorado What is calcium? When a star is on the way to converting all of its carbon and oxygen atoms into [...]
