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Seismometers are instruments that measure motion of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources such as by the use of explosives,railways etc..A simple seismometer that is sensitive to up-down motions of the earth. The three rod in device measure the vibration up to 500 km .It warn the people before the earthquake. This device can differentiate vibration due to train and airplane . It connects with all earthquake center in country. By fixing this device we can prevent the loss of life due to the earthquake. It can warn before 100 secs . In future the warning time of the device will be increase.