File card system and cards therefor

Claim 1

A FILE CARD ADAPTED FOR USE WITH SIMILAR CARDS IN A FILING RECEPTACLE PROVIDING MEANS FOR HOLDING A GROUP OF FILE CARDS UPRIGHT AND IN ALIGNMENT ONE BEHIND THE OTHER, COMPRISING A BODY OF SPRINGY SHEET MATERIAL FOLDED ONCE UPON ITSELF TO FORM A BACK SHEET AND A FRONT SHEET HAVING FREE EDGES OPPOSITE THE FOLD, SAID EDGES CONSTITUTING THE UPPER EDGES, SAID FRONT SHEET BEING FORMED TO PROVIDE REARWARDLY PROJECTING PROTUBERANCES ADJACENT ITS UPPER EDGE AND EXTENDING TOWARD SAID BACK SHEET AND SERVING TO SPACE SAID SHEETS AND BEING FORMED TO PROVIDE FORWARDLY PROJECTING PROTUBERANCES ADJACENT ITS UPPER EDGE SERVING TO SPACE SAID FRONT SHEET FROM THE REAR SHEET OF AN ADJACENT FILE CARD IN THE FILING RECEPTACLE, SAID FORWARDLY AND REARWARDLY PROJECTING PROTUBERANCES BEING EVENLY SPACED ACROSS THE SHEET WITH THE FORWARDLY PROJECTING PROTUBERANCES BEING POSITIONED SUBSTANTIALLY MIDWAY OF THE REARWARDLY PROJECTING PROTUBERANCES WHEREBY A GROUP OF CARDS CAN BE MANUALLY COMPRESSED IN A DIRECTION NORMAL TO THEIR PLANES WITH THE INDIVIDUAL CARDS FLEXING UNDER TENSION.