The invention of the ruler takes us back to the ancient civilizations such as the Greeks and Egyptians.Rulers were used to make measurements in a straight line.The first excavated rulers were often made from wood or ivory.
In the history of measurement many distance units have been used which were based on human body parts such as hand, foot and these units varied in length by era and location.In the late 18th century the metric system came into use and has been adopted to varying degree in almost all countries in the world.
The oldest preserved measuring rod is a copper alloy bar and was found by the German Assyriologist Eckhart Unger.Rulers made of ivory were in use by the Indus valley civilization period .Ian Whitelaw holds that the Mohenjodaro ruler is divided into units corresponding to 1.32 inches.
Anton ullrich invented the folding ruler in 1851.Frank hunt later made the flexible ruler in 1902.The modern 12 inch ruler used today was supposed to equal the length of a man's foot while the width of a man's thumb was equal to 1 inch.The rulers we use today are often made from metal or plastic and can be bent to accommodate objects that are not completely straight.
There are different types of rulers that are used today such as desk rulers, line gauge, protractor, drafting triangle, adjustable triangle, triangular scale ruler
- Lakshmi Priya K
No comments:
Post a Comment