Teaching machine

Claim 1

IN A TEACHING MACHINE, THE COMBINATION OF: FILM MEANS HAVING A SERIES OF FRAMES, EACH FRAME HAVING A FIRST IMAGE AREA FOR A WRITTEN QUESTION AND A SECOND IMAGE AREA COMPRISED OF A NUMBER OF SUBAREAS FOR A PROGRAMMED ANSWER, PROJECTION MEANS FOR PROJECTING THE FIRST AND SECOND IMAGE AREAS OF A FRAME POSITIONED AT A PROJECTION STATION INCLUDING ELECTRICALLY OPERATED INDEXING MEANS FOR MOVING THE NEXT FRAME TO THE PROJECTION STATION WHEN ENERGIZED, DISPLAY MEANS FOR DISPLAYING THE IMAGE PROJECTED FROM THE FIRST IMAGE AREA, AND MULTIPLE CHOICE COMPARISON MEANS COMPRISING A NUMBER OF PHOTOSENSITIVE SWITCHING MEANS CORRESPONDING TO THE NUMBER OF SUBAREAS ELECTRICALLY CONNECTED IN A SERIES CIRCUIT FOR ENERGIZING THE INDEXING MEANS, EACH PHOTOSENTITIVE SWITCHING MEANS BEING POSITIONED TO BE ILLUMINATED BY LIGHT PROJECTED THROUGH THE CORRESPONDING SUBAREAS, THE PHOTOSENSITIVE SWITCHING MEANS BEING ESSENTIALLY NONCONDUCTIVE WHEN IN A FIRST STATE OF ILLUMINATION, AND CONDUCTION WHEN IN A SECOND STATE OF ILLUMINATION, AND A MANUALLY OPERABLE SWITCH MEANS CONNECTED IN SHUNT AROUND EACH PHOTOSENSITIVE SWITCHING MEANS, SAID MULTIPLE CHOICE COMPARISON MEANS IS PROGRAMMED BY OPAQUING OUT ONE OR MORE OF THE SUBAREAS SO AS TO RENDER THE PHOTOSENSITIVE SWITCHING MEANS CORRESPONDING TO THE CORRECT ANSWER NONCONDUCTIVE, CLOSURE OF THE MANUALLY OPERABLE SWITCH MEANS CONNECTED IN SHUNT AROUND THE NONCONDUCTIVE PHOTOSENSITIVE SWITCHING MEANS CAUSING THE INDEXING MEANS TO INDEX THE NEXT FRAME INTO POSITION THEREBY INDICATING A CORRECT ANSWER BY THE STUDENT.