Many different makes of portable grain moisture meters are available. Some work on change in resistance and others work on change in capacitance. When selecting a meter, make sure it is suitable for paddy and polished rice and other crops

The balance scale is such a simple device that its usage likely far predates the evidence. What has allowed archaeologists to link artifacts to weighing scales are the stones for determining absolute mass. The balance scale itself was probably used

A simple microscope is used to see the magnified image of an object. Antonie Van Leeuwenhoek, a Dutch, invented the first simple microscope, consisting of a small single high-powered converging lens to inspect the small micro-organisms of freshwater. It is