Before the advent of the Richter scale scientists used to measure the intensity of the earthquake by the use of the Mercalli Scale. It was invented in the year 1902 and it was basically used to measure the intensity of the Earthquake based on the observation of the destruction which is caused by the calamity on particular location. This intensity is varies from place to place. The distance from the epicenter, the quality and also the design of any construction and the nature of the surface beneath the building are factors responsible for the variation of the intensity of an earthquake from place to place.
The Mercalli scale is said to be more descriptive than the Richter scale which measures the magnitude of the earthquake. The modified type of the Mercalli scale ranges from I to XII. XII is the most severe measure of the quake. The Mercalli provides a measure of the damage on the environment which is measured from VI and above. Examples of this measures are as follows; I) not felt, 4) some disturbance like rattling of windows, 8) the sand and mud may be ejected, 12) there is total damage and waves could be seen on the surface of the ground.
Some of the advantages of the Richter scale over the Mercalli scale are as follows; the Richter can be used to easily compare the magnitudes of the earthquakes regardless of the location of the instrument. The Richter has an open ended scale due to the fact that it is based on the measurement and not description as in the Mercalli scale. The Richter scale employs the logarithmic measure of magnitude. A record of 2.0 on the scale is ten times more powerful compared to the 1.0 record. The 3.0 record is 100 times more powerful. The Richter scale is able to give the energy released at the point of focus and this strength can be measured from the point of the epicenter. The force released when an earthquake takes place is measured by a seismograph.