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Screw – Simple machines – Physics

By | 2017-10-14T16:35:54+00:00 August 17th, 2017|Physics, What|

A cider press with big wooden screws People always count screws as a separate kind of simple machine. But really screws are just one kind of inclined plane. They are such an important kind that we give them their own category. Like most other simple machines, screws also exist in nature. The hip joints of [...]

What is Hinduism? A religion of India

By | 2017-10-14T16:35:20+00:00 July 21st, 2017|India, Religion, What|

Arjuna fighting Karna, with Krishna as his charioteer (Duttapara Temple, ca. 1500s AD) The word Hindu comes from the river Indus, and it just means the people who live near the Indus river (actually in modern Pakistan). The Harappa people who lived near that river about 2500 BC carved images of several different gods on their clay seals. We can't read Harappan writing, [...]

What’s the Ionic order?

By | 2017-10-14T15:17:15+00:00 July 1st, 2017|Architecture, Greeks, What|

Around 500 BC, Greek architectural styles changed so that instead of building temples in the old Doric style, people began to want their new temples for the gods to be built in the new Ionic style. Ionic temples are a little fancier and more delicate than Doric temples, without being as elaborate as Corinthian temples. [...]

Who invented playing cards? China

By | 2017-10-14T16:33:39+00:00 June 23rd, 2017|China, Games, What|

An early playing card (Ming Dynasty, ca. 1500 AD) People in T'ang Dynasty China made the first playing cards, about 800 AD. They used their new material, paper, to make the cards, and they called their game "the leaf game". The emperor's daughter, Princess Tongchang, played cards with her husband's family in the [...]

Where does chocolate come from? South America

By | 2017-10-14T15:18:41+00:00 June 21st, 2017|Food, South America, What|

Cocoa pods grow right from the trunk of the cocoa tree! (Thanks World Cocoa Foundation) Chocolate comes from cocoa beans, which grew on trees in Central America and South America starting probably about 100 million years ago. Cocoa trees may have gotten their start on the lower slopes of the Andes Mountains. Cocoa trees [...]

Who invented knitting? History of clothing

By | 2017-10-14T16:32:50+00:00 June 8th, 2017|Africa, Clothing, What|

Nalbinding hat from Urumchi (ca. 1000 BC) Even before the invention of spinning and weaving, people were making cloth using early forms of knitting we call "nalbinding" or "sprang", which used one needle to hook together short lengths of yarn. Probably people started this early knitting as a way to make fishing nets. [...]

What is Tao? Taoism in Ancient China

By | 2017-10-14T16:34:24+00:00 June 7th, 2017|China, Philosophy, What|

Later portrait of Lao Tzu Taoism is a philosophy or way of life. A man named Lao Tzu (or Lao Tsu) may have started it. He lived a little before Confucius and the Buddha, about 600 BC. Tao means the "way" or the "path". According to the traditional story, Lao Tzu worked as a librarian [...]

Chinese animals – Environment of China

By | 2017-10-14T15:17:59+00:00 June 6th, 2017|China, Environment, What|

A camel caravan in northern China Long ago, in the Stone Age, about 3000 BC, many different kinds of wild animals lived in China - elephants, lions, pandas, wild horses, wolves, wild dogs, aurochs, and many others. But as there got to be more and more people and farms, there was less room. [...]

What is lost wax casting? History of Art

By | 2017-10-14T15:16:41+00:00 May 25th, 2017|Art, What|

A Samnite man cutting the bronze pins off a newly poured lost wax statue. This is the only ancient image of lost wax casting; it's from Pompeii, about 400 BC. Just a little while after bronze was invented, around 2500 BC, the Sumerians began to make bronze jars and bronze cups using lost-wax [...]