How did the time measured in the past and now?

In the past there were several types of hours: sunny, sandy and finally clocks of the classes, more like our clock. Sunclocks measured time in relation to the sun, a stick was sticking to the ground and along the day the sun was in different positions and the shadow fell gradually to the ground in different points, and the time learned. Hourglass measured time with a drop of sand grains in more often than a special form. But there was one problem – this is what the sanding clock needed to follow and turn over to measure time.