Answer checking device

Claim 1

AN ANSWER CHECKING DEVICE COMPRISING A DRUM OF ELECTRICALLY INSULATING MATERIAL, A FIRST AND SECOND STRIP OF ELECTRICALLY CONDUCTING MATERIAL DISPOSED ABOUT THE DRUM PARALLEL TO EACH OTHER AND COAXIALLY OF THE DRUM, A FIRST GROUP, OF FINGERS OF ELECTRICALLY CONDUCING MATERIAL EXTENDING NORMALLY FROM THE FIRST STRIP TOWARD THE SECOND STRIP, SAID FINGERS BEING SPACED FROM EACH OTHER BY EQUAL INCREMENTS, A SECOND GROUP OF FINGERS OF ELECTRICALLY CONDUCTING MATERIAL EXTENDING FROM THE SECOND STRIP TOWARD THE FIRST STRIP, EACH FINGER OF THE SECOND GROUP BEING DISPOSED BETWEEN TWO ADJACENT FINGERS OF THE FIRST GROUP, THE FINGERS OF THE FIRST GROUP BEING ELECTRICALLY CONNECTED TO THE FIRST STRIP AND ELECTRICALLY INSULATED FROM THE SECOND STRIP AND THE FINGERS OF THE SECOND GROUP BEING ELECTRICALLY CONNECTED TO THE SECOND STRIP AND ELECTRICALLY CONNECTED TO THE SECOND FIRST ELECTRICALLY CONDUCTING BRUSH DISPOSED IN SLIDABLE ENGAGEMENT WITH THE FIRST STRIP, A SOURCE OF ELECTROMOTIVE FORCE HAVING FIRST AND SECOND TERMINALS, A FIRST ELECTRICALLY RESPONSIVE INDICATOR ELECTRICALLY CONNECTED BETWEEN THE FIRST BRUSH AND THE FIRST TERMINAL OF THE SOURCE, A SECOND BRUSH OF ELECTRICALLY CONNECTED MATERIAL IN SLIDABLE ENGAGEMENT WITH THE SECOND STRIP, A SECOND ELECTRICALLY RESPONSIVE INDICATOR ELECTRICALLY CONNECTED BETWEEN THE SECOND BRUSH AND THE FIRST TERMINAL OF THE SOURCE, A SWITCH HAVING A FIRST TERMINAL ELECTRICALLY CONNECTED TO THE SECOND TERMINAL OF THE SOURCE AND A SECOND TERMINAL, A PAIR OF ELONGATED CONTACT FINGERS ABUTTING THE DRUM BETWEEN THE TWO STRIPS THEREON AT POINTS ON AN AXIS NORMAL TO THE FINGERS ON THE DRUM AND SPACED BY APPROXIMATELY ONEHALF THE INCREMENT BETWEEN THE FINGERS OF THE FIRST GROUP, SAID FINGERS BEING ELECTRICALLY CONNECTED TO THE SECOND TERMINAL OF THE SWITCH, AND A TAPE OF ELECTRICALLY INSULATING MATERIAL MOUNTED ON THE DRUM BETWEEN THE CONTACT FINGERS AND THE FIRST AND SECOND GROUP OF FINGERS ON THE DRUM, SAID TAPE HAVING A PERFORATION CONFRONTING ONLY ONE OF THE CONTACT FINGERS, WHEREBY CLOSING THE SWITCH COMPLETES AN ELECTRICAL CIRCUIT THROUGH ONLY ONE OF THE INDICATORS.