Clip for flexible sheet

Claim 1

A CLIP FOR SHEET MATERIAL COMPRISING A SHELL COMPOSED OF A REAR FLANGE AND FIRST AND SECOND MEMBERS ARRANGED TO EXTEND FORWARDLY OF SAID REAR FLANGE, SAID FIRST MEMBER BEING OF THE SAME WIDTH AS SAID FLANGE, SAID EXTENDING FORWARDLY THEREFROM ON ONE SIDE OF THE PLANE OF SAID FLANGE, SAID FIRST MEMBER HAVING A FRONT PORTION THEREOF CURVED INWARDLY THROUGH AN ANGLE EXCEEDING 180* TOWARDS AND THROUGH THE SAID PLANE OF SAID FLANGE, THE EXTREME END OF SAID CURVED FRONT PORTION BEING FORMED WITH A LIP SO THAT, WHEN VIEWED FROM THE SIDE, SAID FIRST MEMBER IS SIMILAR TO THE TOP OF A SHEPHERS''S CROOK, SAID SECOND MEMBER BEING OF THE SAME WIDTH AS SAID FIRST MEMBER AND EXTENDING FORWARDLY FROM SAID FLANGE ON THE OTHER SIDE OF THE SAID PLANE, SAID SECOND MEMBER HAVING A FORWARD END PORTION THEREOF CURVED AWAY FROM SAID FIRST MEMBER AND SAID PLANE, AND A CORE COMPOSED OF A STRIP OF MATERIAL ADAPTED TO HAVE SHEET MATERIAL WRAPPED AROUND IT AND TO BE INSERTED EDGEWISE INTO SAID SHELL THROUGH A SLOT-LIKE GAP DEFINED BY SAID LIP OF SAID FIRST MEMBER AND SAID FORWARD END OF SAID SECOND MEMBER, SAID CORE BEING UNATTACHED TO SAID SHELL AND BEING OF A WIDTH GREATER THAN THE WIDTH OF SAID SLOT-LIKE GAP WHEREBY THE REAR PORTION OF SAID CORE IS SEATED ON SAID FORWARD END PORTION OF SAID SECOND MEMBER, SAID SHEET EXTENDING OUT OF SAID CLIP FROM BETWEEN SAID FORWARD END PORTION OF SAID SECOND MEMBER AND SAID CORE PORTION SEATED THEREON SO THAT, WHEN TENSION IS APPLIED TO SAID SHEET, THE FRONT EDGE OF SAID CORE AND SAID SHEET WRAPPED THEREAROUND ARE PULLED INTO SAID CURVED FRONT PORTION OF SAID FIRST MEMBER AND SAID SHEET IS FIRMLY GRIPPED.