Visual education device for illustrating mathematical concepts

Claim 1

A MATHEMATICAL DEVICE FOR VISIBLY ILLUSTRATING VARIOUS MATHEMATICAL OPERATIONS INCLUDING THE ILLUSTRATIONS OF PLACE VALUE IN TEACHING NUMERATION OF NUMBERS TO A GIVEN BASE INCLUDING THE BASE 12 COMPRISING, (A) A PLURALITY OF SIMILAR BASIC HOLDERS, (B) EACH OF SAID HOLDERS INCLUDING A RECTANGULAR BLOCK HAVING A SERIES OF RECEPTACLES DISPOSED IN TWO ROWS ON SAID BLOCK, EACH ROW INCLUDING FIVE RECEPTACLES, EACH BEING DISPOSED IN A SIDE-BY-SIDE RELATIONSHIP, SAID RECEPTACLES BEING UNIFORMLY SPACED THEREON, (C) SAID BLOCK HAVING OPPOSED EDGE PORTIONS, AND (D) SAID BLOCKS EACH HAVING COMPLEMENTARY INTERLOCKING MEANS FORMED ON THE RESPECTIVE EDGE PORTIONS THEREOF WHEREBY SAID BLOCKS CAN BE DETACHABLY CONNECTED ONE TO ANOTHER, (E) A SERIES OF INDICIA MEANS ADAPTED TO BE INSERTED INTO THE RECEPTACLES OF SAID BLOCKS TO SET UP VARIOUS MATHEMATIC OPERATIONS, (F) A PLURALITY OF SIMILARLY MADE AUXILIARY HOLDERS, EACH OF SAID AUXILIARY HOLDERS HAVING A PAIR OF RECEPTACLES ONLY FORMED THEREIN, (G) AND SAID AUXILIARY HOLDERS HAVING COMPLEMENTARY INTERLOCKING MEANS FOR DETACHABLY CONNECTING THE SAME TO SAID BASIC HOLDERS WHEREBY SAID BASIC HOLDER AND AUXILIARY HOLDER ARE DISPOSED IN A COMMON PLANE WHEREIN THE RECEPTACLES IN SAID BASIC HOLDER AND SAID AUXILIARY HOLDER ARE DISPOSED IN ALIGNMENT IN THE ASSEMBLED POSITION THEREOF.