Teaching machine

Claim 1

IN A TEACHING MACHINE FOR SUPPLYING A PLURALITY OF STUDENTS AT INDIVIDUAL STUDY AREAS WITH AUDIBLE INSTRUCTIONAL MATERIAL AND INCLUDING A SOUND REPRODUCER AT EACH OF SAID STUDY AREAS, THE COMBINATION COMPRISING MEANS REMOTE FROM SAID STUDY AREAS HAVING A PLURALITY OF MASTER PROGRAM OUTPUT LINES ON WHICH RESPECTIVELY APPEAR A CORRESPONDING PLURALITY OF MASTER PROGRAM SIGNALS AND WHICH MASTER PROGRAM OUTPUT LINES ARE DIVIDED INTO A NUMBER OF GROUPS, A DIAL MEANS ASSOCIATED WITH EACH STUDY AREA AND INCLUDING A MANUALLY OPERABLE DIAL AT SAID STUDY AREA FOR PRODUCING TRAINS OF DIAL PULSES IN RESPONSE TO MANIPULATION OF SAID DIAL BY A STUDENT, A LINEFINDER, LINE MEANS CONNECTING EACH OF SAID DIAL MEANS TO SAID LINE-FINDER, FIRST SELECTING MEANS RESPONSIVE TO THE RECEIPT OF A TRAIN OF DIAL PULSES FOR SELECTING ONE OF SAID GROUPS OF PROGRAM OUTPUT LINES, SECOND SELECTING MEANS RESPONSIVE TO THE RECEIPT OF A TRAIN OF DIAL PULSES FOR SELECTING ONE OF THE PROGRAM OUTPUT LINES FROM THE GROUP SELECTED BY SAID FIRST SELECTING MEANS, MEANS OPERABLE IN RESPONSE TO A SIGNAL PRODUCED BY A CALLING DIAL MEANS TO START SAID LINE FINDER IN OPERATION AND TO CAUSE THE SAME TO LOCK ON THE CALLING DIAL MEANS SO THAT TRAINS OF DIAL PULSES FROM SAID CALLING DIAL MEANS MAY PASS THERETHROUGH, MEANS FOR ROUTING THE FIRST TRAIN OF DIAL PULSES PASSING THROUGH SAID LINE-FINDER TO SAID FIRST SELECTING MEANS TO CAUSE THE SELECTION OF A GROUP OF PROGRAM OUTPUT LINES AND FOR ROUTING THE NEXT TRAIN O/F DIAL PULSES TO SAID SECOND SELECTOR MEANS TO CAUSE THE SELECTION OF ONE PROGRAM OUTPUT LINE FROM SAID SELECTED GROUP, AND A PLURALITY OF CIRCUITS EACH EXCLUSIVELY ASSOCIATED WITH A RESPECTIVE ONE OF SAID STUDY AREAS AND BY-PASSING SAID LINEFINDER FOR CONNECTING THE ONE PROGRAM OUTPUT LINE SELECTED BY OPERATION OF ONE OF SAID DIAL MEANS TO THE SOUND REPRODUCER ASSOCIATED WITH SAID ONE DIAL MEANS.