A device for making a continuous measurement of the angle and direction of borehole [[deviation]] during a [[survey]]. A pendulum moves the wiper arm of a potentiometer so that a simple [[resistance]] measurement corresponds with the position of the pendulum and therefore the angle between the tool axis and verticle. A compass moves the wiper arm of another potentiometer so that another resistance measurement corresponds to a measure of [[azimuth]]. Another pendulum moves the wiper of a third potentiometer to make a measurement of [[relative bearing]]. See [[deviation]], [[azimuth]], and [[relative bearing]]. Used in [[dipmeter]] surveys. Compare [[photoclinometer]].