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Parchment and the history of books

By |2019-06-01T13:54:12-07:00July 27th, 2017|Literature, West Asia|

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 BC most people in West Asia and the Mediterranean used papyrus for writing. What is papyrus? Making papyrus Invention of writing Who invented the alphabet? All our West [...]

Rangoli – Colored patterns – Hinduism project

By |2018-04-16T10:32:23-07:00July 21st, 2017|India, Religion|

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 in India call these patterns rangoli After the celebration, they just sweep up and the floor is clean again. You can make your own rangoli [...]

Calcium project – Chalk and lemon juice – Chemistry

By |2019-02-26T05:52:48-07:00June 1st, 2017|Chemistry|

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 the kind in the picture. Some kinds of chalk are made of plaster of paris. You don't want those. What is calcium? More [...]

Calcium – Atoms and Chemistry

By |2019-02-26T05:37:02-07:00June 1st, 2017|Biology, Chemistry|

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 iron, calcium is one kind of atom it makes along the way. More about stars And about atoms All our chemistry articles What's [...]