I learned this today. Smallpox was responsible for as many as 500 million deaths in the 20th century, but it was completely eradicated by December 1979. Smallpox is a disease caused by four orthopoxviruses. They are variola, vaccinia, cowpox, and monkeypox. Variola only infects humans while the other viruses can infect other animals as well. […]
#114 What happened to smallpox? Read More »
I learned this today. Thomas Edison used thin strips of bamboo in his early light bulbs because carbonized bamboo has a very high electrical resistance. When Edison started trying to improve the light bulb, there were two basic forms of light available: arc lights and incandescent lights. An arc light is one that makes light
#113 Why did Thomas Edison use bamboo in his light bulb? Read More »
I learned this today. The first evidence for a wedding ceremony between a man and a woman is from Mesopotamia in 2350 BC. In the time of hunter-gatherers, people lived in small groups, probably of about thirty people. Each group would have several male leaders who shared the women. They would all care for and
#112 When did people first start getting married? Read More »
I learned this today. The International Prototype of the Kilogram, kept in Paris, is not accurate enough to be the standard for all kilograms around the world. Different measures for different things have been used around the world since people began measuring things. These measurements were usually related to the human body or common things
#108 Why is the official kilogram in France no longer used? Read More »
I learned this today. Adolf Hitler had three brothers, two sisters, one half-brother, and one half-sister. Because of the things he did, it is difficult to see Hitler as a real person, but of course he was, and he has a family. Adolf Hitler was born on April 20, 1889, to Alois Hitler and Klara
#107 Did Adolf Hitler have any brothers or sisters? Read More »
I learned this today. Vikings is the name given to the seafaring people from Scandinavia who raided through Europe from the late 8th century to the late 11th century. The Vikings didn’t call themselves “Vikings” and the word wasn’t used to refer to all of the people and the time period until the early 18th
#105 Why do we use the word Vikings? Read More »
I learned this today. Shoe sizes in America and the UK are measured in barleycorns. Nobody knows when people first started wearing shoes, but experts think it might have been about 40,000 years ago. The little toe bones of skeletons found after 40,000 years ago are thinner than the bones found before. They deduce that
#103 Why do we use those measurements for shoe sizes? Read More »
I learned this today. The mile we use today originated with the Roman mile which was one thousand paces. The word “mile” comes from “mille passus”, which means 1,000 paces. Ancient measuring systems all began by using body parts to measure things. The oldest unit of length is the Egyptian cubit, although they didn’t call
#102 Why do we use miles as a unit of measurement Read More »
I learned this today. Wire fraud and mail fraud are federal crimes in the United States that concern transferring something connected to fraud by mail, email, phone, radio, or television. To be guilty of wire fraud, somebody must have “voluntarily and intentionally devised or participated in a scheme to defraud another out of money” and
#97 What are mail fraud and wire fraud? Read More »
I learned this today. There is evidence of a dentist from 12,000 BC. Before humans took up agriculture, possibly about 12,000 years ago, we were hunter-gatherers and we had less tooth decay than when we became farmers. Researchers were able to extract dental plaque from the teeth of 34 prehistoric European skeletons. Dental plaque is
#96 When was the first dentist? Read More »
