Compasses with improved adjustment means

Claim 1

A COMPASS COMPRISING A PAIR OF ARMS MOVABLE RELATIVE TO ONE ANOTHER, A THREADED ROTATABLE SPINDLE ADJUSTABLY CONNECTING SAID ARMS TO ONE ANOTHER, THE THREADES OF SAID SPINDLE BEING RELATIVELY RIGID, A NUT MOUNTED WITHIN AT LEAST ONE OF SAID ARMS IN ENGAGEMENT WITH THE THREADS OF SAID SPINDLE, SAID NUT HAVING A THREAD AREA ADAPTED TO COOPERATE WITH THE THREADS ON SAID SPINDLE FOR ADJUSTING THE POSITIONS OF SAID ARMS RELATIVE TO ONE ANOTHER UPON ROTATION OF SAID SPINDLE, THE THREAD AREA OF SAID NUT COMPRISING A HOMOGENEOUS RESILIENT MATERIAL HAVING PORTIONS PROTRUDING INTO THE RELATIVELY RIGID THREADS OF SAID SPINDLE, SAID RESILIENT MATERIAL BEING CONSTRUCTED TO YIELD TEMPORARILY IN RADIAL DIRECTIONS RELATIVE TO THE THREAD OF SAID SPINDLE IN RESPONSE TO THE APPLICATION OF FORCES ALONG THE AXIAL DIRECTION OF SAID SPINDLE AND TO RESILIENTLY RESUME ITS ORIGINAL PROTRUDING CONDITION RELATIVE TO THE RIGID THREADS OF SAID SPINDLE UPON REMOVAL OF SAID AXIAL FORCES, WHEREBY SAID SPINDLE AND NUT MAY BE SLIDABLY MOVED RELATIVE TO ONE ANOTHER BY TEMPORARY DEFORMATION OF SAID RESILIENT MATERIAL UPON MANUAL MANIPULATION OF SAID ARMS TOWARD AND AWAY FROM ONE ANOTHER THEREBY TO PERMIT MAJOR ADJUSTMENTS IN THE POSITIONS OF SAID ARMS RELATIVE TO ONE ANOTHER WITHOUT ROTATION OF SAID SPINDLE.