A gyrocompass is a continuously-driven gyroscope which acts as a compass. It is unaffected by magnetic variations and is used for steering large ships. As the Earth rotates the gyroscope experiences a torque if it is out of the meridian. The resulting tilting is sensed by a gravity sensing system which itself applies a torque to the gyroscope which returns it to the north-south meridian. The sensitivity of such systems decreases with latitude away from the equator.