How does a clock run?

Many clocks and watches today are run by electricity.  But the most common type of clock, the spring or wind-up clock, is powered by the gradual uncoiling of a steel spring, which moves a series of gears, or wheels. 

The movement turns the hands that point to the hours and minutes on the clock’s face.

When you wind a clock, you are coiling the mainspring.  The spring is mounted on a large gear wheel.

As soon as the spring is wound up tight, it begins to unwind.  As the spring unwinds it turns the gear wheel, which causes the other wheels and parts in the clock’s mechanism to move.

Two special wheels, called the escape wheel and the balance wheel, keep the spring from unwinding too fast and make the wheels turn at an even rate of speed.

As the wheels turn, the movement slowly turns the hands that point to the hours and minutes on the clock’s face.

Watches are really small clocks.  A watch may have as many as 160 different parts.–Dick Rogers

Why do we say A.M. and P.M. when telling time?

The  letters A.M (ante meridian) P.M (post meridian) tell us  what part of the day it is on a 12 hour clock. 

As we all know, there are 24 hours in a day but only 12 hour numbers on a clock.  This is because in  most  countries the hours of the day are usually divided into two parts  for  timekeeping..

We call the  first  part  of the day  a.m. the second part p.m.

The  first clued clocks did  not keep  good time.  They had to be set every  day at noon, when the  sun  was at the  meridian, or the  highest point in the sky.

From  this we began to call the morning  part of the day a.m., meaning ”ante meridian.” or before noon.  P.M. means “post meridian” or after noon.

If every  town set its  clocks  by the sun today, few  places would  be on  the  same time.  When it is noon  in  one town, it is not yet noon in a town a few miles east.  For this reason. the world is divided into time zones.   All the clocks in a time zone are set  the same time.-Dick Rogers