Data processing apparatus

Claim 1

IN COMBINATION, A STACK OF RECORD CARDS HAVING SUBSTANTIALLY IDENTICAL DIMENSIONS AND SUPPORTED WITH THE UPPER EDGE OF EACH CARD DISPOSED IN A SUBSTANTIALLY HORIZONTAL POSITION, EACH OF SAID UPPER EDGES INCLUDING SUCCESSIVE PAIRS OF NOTCHES ALIGNED IN ROWS ALONG THE DEPTH OF SAID STACK, EACH NOTCH PAIR CONTAINING A NOTCH OF A FIRST AND OF A SECOND KIND SEQUENCED IN ACCORDANCE WITH A FIRST OR A SECOND BINARY DIGIT REPRESENTED BY SAID NOTCH PAIR, THE SIDE EDGES OF RESPECTIVE CARDS EACH INCLUDING A SLOT LOCATED NEAR SAID UPPER EDGE, CORRESPONDING ONES OF SAID SLOTS BEING ALIGNED IN ROWS ALONG THE DEPTH OF SAID STACK, A PLURALITY OF PAIRED SELECTION RODS EACH EXTENDING TRANSVERSE TO SAID UPPER EDGES THROUGH A ROW OF NOTCHES AND BEING ADAPTED TO ASSUME FIRST AND SECOND ROTATIONAL POSITIONS SUBSTANTIALLY 45* APART, EACH OF SAID SELECTION RODS HAVING A CROSS-SECTION ADAPTED TO ENGAGE ONLY NOTCHES OF SAID SECOND KIND IN CARD-RETAINING RELATIONSHIP AND ONLY WHEN SAID ROD IS IN SAID SECOND ROTATIONAL POSITION, A PAIR OF SUBSTANTIALLY IDENTICAL, ROTATABLE HOLDING RODS PARALLEL TO SAID SELECTING RODS, SAID HOLDING RODS BEING NORMALLY POSITIONED TO ENGAGE SAID ROWS OF SLOTS IN SUPPORTING RELATIONSHIP SUCH THAT SAID SELECTION RODS ARE OUT OF CONTACT WITH THE NOTCHES THROUGH WHICH THEY EXTEND, FIRST POSITIONING MEANS FOR NORMALLY MAINTAINING EACH PAIR OF SELECTION RODS IN A FIRST STATE, THE INDIVIDUAL RODS OF EACH PAIR IN SAID FIRST STATE ASSUMING FIRST AND SECOND ROTATIONAL POSITIONS RESPECTIVELY ADAPTED TO RELEASE NOTCH PAIRS REPRESENTATIVE OF SAID FIRST BINARY DIGIT, SAID FIRST POSITIONING MEANS BEING RESPONSIVE TO A CODED SELECTION SIGNAL FOR ROTATING ADDRESSED SELECTION ROD PAIRS TO A SECOND STATE, THE INDIVIDUAL RODS OF EACH PAIR IN SAID SECOND STATE ASSUMING SECOND AND FIRST POSITIONS RESPECTIVELY ADAPTED TO RELEASE NOTCH PAIRS REPRESENTATIVE OF SAID SECOND BINARY DIGIT, AND SECOND POSITIONING MEANS FOR ROTATING SAID HOLDING RODS OUT OF ENGAGEMENT WITH SAID SLOTS TO RELEASE A SINGLE CARD ADDRESSED BY SAID SELECTION SIGNAL.