Direction finder

Claim 1

A NAVIGATIONAL INSTRUMENT FOR DETERMINING COURSE DIRECTIONS IN RESPECT TO A NAVIGATIONAL CHART, COMPRISING AN ELONGATED DOUBLE RECTANGULAR BASE HAVING A PLURALITY OF CLOSELY SPACED PARALLEL GRADUATIONS TO PERMIT THE INSTRUMENT TO BE PLACED UPON AND CORRECTLY LINED UP ON A NAVIGATIONAL CHART, AN INTERMEDIATE ROTATABLE COMPASS DIAL MOUNTED BETWEEN THE DOUBLE PLATE TO GIVE THE CORRECT HEADING AND A SUPERIMPOSED MOVABLE COURSE ARROW HAVING A SEMI-CIRCULAR BASE TO BE DIRECTED TO THE NEXT POINT ON THE COURSE AND TO GIVE THE PROPER COURSE HEADING IN RESPECT TO SAID DIAL, SAID RECTANGULAR BASE CONSISTING OF TOP AND BOTTOM ELONGATED PLASTIC RECTANGULAR MEMBERS JOINED AT THEIR EDGES AND SAID COMPASS DIAL BEING ROTATABLY MOUNTED BETWEEN SAID MEMBERS AND HELD IN ADJUSTED POSITION BY FRICTION BETWEEN SAID MEMBERS, AN EYELET ACTING AS A PIVOT CENTER AND HOLDING SAID RECTANGULAR MEMBERS, SAID COMPASS DIAL AND SAID SEMI-CIRCULAR BASE CLOSELY TOGETHER TO CAUSE FRICTIONAL RETENTION OF THE COMPASS DIAL AND A WINDOW ABOVE THE PERIPHERY OF THE DIAL AND BELOW THE SEMICIRCULAR BASE OF THE ARROW ON THE TOP MEMBER TO PERMIT ADJUSTMENT OF SAID COMPASS DIAL, AND SAID ARROW HAVING OBLIQUE SIDEES TO FORM A POINT AWAY FROM THE EYELET AND SAID SPACED GRADUATIONS EXTENDING PARALLEL TO EACH OTHER THE FULL LENGTH OF THE RECTANGULAR BASE TRANSVERSE TO THE LONG DIMENSION THEREOF BUT OMITTED FOR A SHORT SPACE ON EACH SIDE OF THE EYELET AND THE EDGES OF THE DIAL BEING RADIALLY GRADUATED AND THE OBLIQUE SIDES OF THE ARROW ALSO BEING RADIALLY GRADUATED.