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There is an ancient inventio...

There is an ancient invention still used in some parts of the world today that allows people to see through walls. What is it?

Correct answers: 49

The first user who solved this task is Djordje Timotijevic.

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Brian Regan: Pick Somebody at Random

You know whats fun? You pick somebody at random, like out of the phone book, and send them about 100 Just Because cards. They cant even ask you why you did it.

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Charles Gerhardt

Died 19 Aug 1856 at age 39 (born 21 Aug 1816). Charles (-Frédéric) Gerhardt was a French chemist who, with Auguste Laurent, developed a classification of organic compounds. Like most chemists he was aware that the dualistic system of Jöns Berzelius was unsatisfactory and tried to create an alternative. He adopted what became known as type theory in which he thought all organic compounds were based on four main types - hydrogen, hydrogen chloride, ammonia, and water. Organic compounds were referred to these types by replacing a hydrogen atom in one of these compounds by a radical (i.e., by a group of atoms). His idea was opposed by his contemporaries and was later abandoned, but it proved important in the subsequent rationalization of structural organic chemistry.

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