Time for Change

Since 1761, timekeeping has significantly changed.  In 1900, pendulum clocks had been finely tuned so as to only be off by 1/100 of a second each day.  In the '20s, scientists discovered quartz crystals could keep even more accurate time than a pendulum and were only off about 1/500 of a second each year.  Half way through the 20th century, atomic clocks were built that would only be off by one second every 300 million years.   Who really needs a clock that accurate? 

    It is evident that times have certainly changed.  Clocks have made major leaps and bounds since the days of the shadow clock.  Now we have accurate, reliable clocks that we can use day and night.   Some of our clocks will run for years without so much as a change of batteries or a twist of a little knob.  We have certainly developed the concept of time and incorporated it into every moment of our lives.