Gyroscopic compasses

Claim 1

A COMBINATION FOR ORIENTING AND LEVELLING THE DIRECTIVE MEMBER OF A GYROSCOPIC COMPASS DURING START-UP CONDITIONS IN WHICH THE COMPASS INCLUDES A RING MOUNTED TO MOVE ABOUT A VERTICAL AXIS, A CIRCUIT CONNECTING THE MEMBER TO THE RING IN FOLLOW-UP RELATION HAVING A SERVOMOTOR CONNECTED TO MOVE THE RING, A PENDULOUS YOKE MOUNTED ON THE RING WITH FREEDOM ABOUT A NORMALLY HORIZONTAL AXIS, A GIMBAL MOUNTED ON THE YOKE WITH FREEDOM ABOUT A NORMALLY HORIZONTAL AXIS PERPENDICULAR TO THE AXIS OF THE YOKE ON WHICH THE MEMBER IS MOUNTED WITH FREEDOM ABOUT A NORMALLY VERTICAL AXIS; MEANS INCLUDING A NORMALLY OPEN CIRCUIT FOR CAGING THE MEMBER AND GIMBAL TO THE YOKE, MEANS INCLUDING A NORMALLY OPEN CIRCUIT FOR PROVIDING AN ORIENTING INPUT TO THE SERVOMOTOR, NORMALLY INEFFECTIVE MEANS FOR OPENING THE FOLLOW-UP CIRCUIT, MEANS FOR SIMULTANEOUSLY CONDITIONING THE CAGING AND ORIENTING CIRCUITS FOR OPERATION AND FOR RENDERING THE FOLLOW-UP CIRCUIT OPENING MEANS EFFECTIVE, AND MEANS OPERABLE UPON RESTORATION OF THE CAGING, ORIENTING AND FOLLOW-UP CIRCUITS TO NORMAL CONDITION TO LEVEL THE ORIENTED MEMBER WITH RESPECT TO THE GIMBAL AXIS.