Updated: 8:29 PM UTC, Jul 16, 2017

Should You Wake Up a Sleepwalker?

You have probably heard that it is dangerous to wake up a sleepwalker. This is decidedly false, and it is at times preferable to wake the person up rather than let the individual face danger. Upon waking up, the sleepwalker may be disoriented, but will react as any other sleeper suddenly awakened.

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Louis Pasteur And The Invention Of Vaccine

It was not Louis Pasteur who invented the principle of vaccine, but Edward Jenner. He had observed that farm laborers in contact with cows developed a natural immunity against human smallpox.

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A Castle’s Spiral Staircase Was a Defensive Measure

In medieval times, a castle’s spiral staircase were usually made of stone and rose in a clockwise fashion when looking up from the bottom. So this way, the attacking swordsmen ascending the stairs, would have his swing blocked by the wall.

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There Is No Robespierre Street in Paris - Strange Isn't It?

Maximilien de Robespierre, a central figure of the French Revolution, does not have any avenue, street, nor even an alley that uses his name in Paris. In 2009, by a narrow majority, the city council rejected a proposal to name a square or street "Robespierre".

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Why Do Casino Dealers Have No Pockets?

Casino staff, especially the dealers, have no jacket or pant pockets to avoid concealing cards, tokens or dice.

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Wearing Green on Stage - Is It Really a Sign of Bad Luck?

While it is common knowledge that wearing green on stage brings bad luck, do you know the origins of this superstition? First of all, during the 18th century green dye contained arsenic, and Molière, the famous playwright, died while clad in green.

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Colds and Drafts

The common cold, contrary to popular belief, is not caused by exposure to drafts or cold air but solely by contamination (coughs, sneezes, contact with saliva or nasal secretions).

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The Role of Catapults on Aircraft Carriers

Planes aboard aircraft carriers do not take off due solely to their propulsion power, as the length of the deck may be too short. Steam-powered catapults assist planes in reaching the speed necessary to take off.

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Do You Know Why We Say “Set the Table”?

This expression dates back to the Middle Ages: the Lord of the manor would invite so many guests that often times the table would be too small.The quick fix was to set planks upon wooden trestles. In order to hide the rustic appearance of the table large covers would be draped or set upon it.

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The Two Color Rule in Table Tennis

The two color rule was initiated in July 1986, stating that one side of the racket rubber must be red and the other side black. This measure was introduced because of the increased use of "combination" rackets, notably during a European championship game when the winner had used a racket whose sides were both red.

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Rocco Siffredi - Why Did He Choose That Name?

The porn movie actor Rocco Siffredi chose his name as a tribute to the macho character played by Alain Delon in the film Borsalino. His real name is Rocco Tano.

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The Symbolism of the Flag of the United Kingdom

The flag of the United Kingdom, also known as  the Union Jack, symbolizes 3 of the 4 countries of which it is composed: Scotland, England, Wales, and Northern Ireland. In fact, it is composed of a juxtaposition of the flags of Scotland, England, and St Patrick’s Cross, the patron saint of Ireland.

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