Set of building blocks wherein each block has connecting means on three surfaces thereof

Claim 1

IN A SET OF BUILDING BLOCKS, THE COMBINATION OF A PLURALITY OF HOLLOW BLOCKS OF SEVERAL PREDETERMINED GEOMETRICAL SHAPES, EACH BLOCK HAVING WALLS WHICH DELIMIT ITS SHAPE, THE BLOCK WITH THE LEAST NUMBER OF WALLS HAVING NO LESS THAN THREE WALLS, THE BLOCK WITH THE GREATEST NUMBER OF WALLS HAVING NO MORE THAN SIX WALLS, EACH OF SAID BLOCKS HAVING AT LEAST ONE WALL BUT NO MORE THAN TWO WALLS WHICH EMBODY A PLURALITY OF TONGUES AND GROOVES OF RIGHT SECTION, ENABLING JOINING THE BLOCKS WALLTO-WALL BY ENGAGEMENT OF THE TONGUES ON A WALL OF ONE BLOCK WITHIN THE GROOVES ON A WALL OF ANOTHER BLOCK WHILE PERMITTING RELATIVE DISPLACEMENT OF THE JOINED BLOCKS IN THE PLANE OF THE ADJOINING WALLS, ONE OF THE REMAINING WALLS CONTAINING A HOLE PERPENDICULAR TO ITS SURFACE, AND ANOTHER MOUNTING A PIN PERPENDICULAR TO ITS SURFACE, SAID PIN CORRESPONDING SUBSTANTIALLY IN DIAMETER TO SAID HOLE, SAID HOLE AND PIN ENABLING JOINING THE BLOCKS WALL-TO-WALL BY ENGAGEMENT OF THE PIN ON A WALL OF ONE BLOCK WITHIN A HOLE IN THE WALL OF ANOTHER BLOCK WHILE PERMITTING RELATIVE ROTATION OF THE BLOCKS ABOUT AN AXIS PERPENDICULAR TO THE PLANE OF THE ADJOINING WALLS, SAID TONGUES AND PINS BEING HOLLOW EXTENSIONS OF THE HOLLOW INTERIOR OF THE BLOCKS AND ELASTICALLY INTERENGAGEABLE WITH THE GROOVES AND HOLES, RESPECTIVELY.