In the basic mouldboard plough the depth of the cut is adjusted by lifting against the runner in the furrow which limited the weight of the plough to what the ploughman could easily lift. These ploughs were fragile and were unsuitable for breaking up the heavier soils of northern Europe. The introduction of wheels to replace the runner allowed the weight of the plough to increase and in turn allowed the use of a much larger mouldboard that was faced with metal. These heavy ploughs led to greater food production and eventually a significant population increase around 600 AD.
The Hourglass 9th Century AD
Since the hourglass was one of the few reliable methods of measuring time at sea it has been said that it was in use as far back as the 11th century it would have complemented the magnetic compass as an aid to navigation. It is not until the 14th century that evidence of their existence was found, appearing in a painting by Ambrogio Lorenzetti 1328. The earliest written records come from the same period and appear in lists of ships stores. From the 15th century onwards they were being used in a wide range of applications at sea, in the church, in industry, and in cookery. They were the first dependable, reusable, and reasonably accurate measure of time.
The Mechanical Clock 13th Century AD
The origin of the all-mechanical escapement clock is unknown the first devices may have been invented and used in monasteries to toll a bell that called the monks to prayers. The first mechanical clocks to clear references exist were large weight driven machines fitted into towers and known today as turret clocks. These early devices struck only the hours and did not have hands or a dial.
* Waterwheel- a machine for converting the energy of free flowing or falling water into useful forms of power
* Windmill - used to generate electricity
* Compass -An instrument containing a magnetized pointer that shows the direction