Modern clocks:

A power source, a pace regulator and the time showing device make up a modern clock.  "Cloche" in French, meaning "bell" is modified and "clock" comes out.  100-1300 AD in Europe (others argued in China) that the first clock that used gravity pulled weights to move gears which led to the action of its "hands" was developed.  Clock towers were built and the Strasbourg Cathedral was its pioneer built between 1352-1354, and it is still working today.  More accuracy were needed and the minute hand was invented by Jost Burgi for Tycho Brahe for astronomical use.  The pendulum was put into clocks in 1656 to improve on the pace.  The first "portable time piece" was introduced by Peter Henlein in Nuremberg, Germany in 1504.  However, it only worked when placed flat which marked its failure.  More investigation was made  by George Graham in 1721 with details of "one second a day" and "a hundredth of a second a day".  The first wrist watch was finally available in the 1800's by the Rolex Oyster, which is the basis for all others nowadays.

Is this good enough?

Basically yes, just that they might run out of batteries!

control of our brain about our skull major parts of our brain different views of our brain why do we dream? what about nightmares? what about recurring dreams? how to remember our dreams? what do my dreams mean? what about televisions? air conditioners? light bulbs? telephones? clocks? computers?  refrigerators? microwave ovens? Chinese culture? who are the authors?games zone