Abstract: A level sensing system for use with an excavating machine includes a light receiving sensor, mounted on the dipper stick of the machine, and an inclinometer, also mounted on the dipper stick of the machine. The sensor and inclinometer provide indications of the relative location of a beam of light and the inclination of the dipper stick. The inclinometer includes a gyroscopic inclination sensor and an accelerometer arrangement for sensing acceleration due to gravity and providing a static vertical reference. A position determining circuit is responsive to the sensor and the inclinometer and calculates the position of a pivot joint on the dipper stick to which a digging bucket is attached. The beam of light is a beam of laser light which is projected by a laser transmitter. An angle-measuring sensor may be provided for measuring the angular orientation between the dipper stick and a cutting edge of the bucket.