Why Onions Make You Cry?

When a fresh onion is sliced, a gas called
propanethiol-S is released into the air. When the gas reaches
the eye, it mixes with the water in the eye to form a weak acid.
This acid irrates the eye and causes the tear producing glands
to flood the eye with water in attempt to wash away the irritant.
These tears make it appear that the person slicing the onion is
crying.

Why The Keys On A Typewriter
Are Arranged So Strangely?

The very first typewriter did not use the
present-day key arrangement but instead used a straight alphabetic
design reading left to right and top to bottom. However, a problem
soon arose with the design because it placed the most frequently
used keys close together, and when a fast typist used the machine,
the printing spokes for these keys would get jammed. To correct the
problem, an inventor named Christopher Sholes designed the current
arrangement, which places the most frequently used keys further apart.

Why Oysters Make Pearls?

The type of oysters that make pearls
spend most of their time on the sandy bottoms of tropical seas. When
a grain of sand, or other foreign particle, gets inside of the oyster's
shell and becomes an irritant, the oyster's system automatically begin's
coating the particle with a protective layer of nacre-mother-of-pearl.
As layer after layer is added, the pearl is formed.

Why Zero Scores In Tennis Are
Called love?

Since early In France, where tennis first
became popular, a big round zero on the tennis scoreboard looked like
an egg and was, called egg, which in French is l'oeuf. When tennis
became popular in this country, Americans copied the French and also
called the zero score l'oeuf but pronounced it love.

Why Races Have First, Second, And Third Prizes?

The practice is the result of a silversmith's
inability to satisfy his customers. In early seventeenth century in Chester,
England, the sheriff agreed to provide a silver trophy for a horse race
and contracted with a silversmith to do the work. The silversmith's first
trophy was unacceptable, and was sent back for another. The second one,
too, was unsatisfactory, and he was instructed to try a third time.
The third trophy was fine, but now the sheriff had three trophies instead
of one. So as not to be wasteful the sheriff decided to award trophies to
first, second, and third place winners.