170 SIMILAR GROUND WORK TO THE THREE FOREGOING DIAGRAMS. THE LITTLE PENTAGONS GOVERN THE DESIGN.
171 DESCRIBE THE CIRCUMFERENCES AS IN PLAN, AND INSCRIBE THE DECAGONAL STAR. THE SMALL DECAGONS IN THE CENTRE OF THE TRIANGLES OF THE PLAN, BY EXTENDED LINES, FORM THE ROSETTE.
172 DIVIDE AS IN PLAN. UPON THE LESSER SIDE TRACE AN ISOCELES TRIANGLE. BY THE APEX OF THE TRIANGLE TRACE A CIRCUMFERENCE, IN WHICH TAKE THE DIAGONALS OF THREE IN THREE DIVISIONS.