Night answering and transfer of trunk calls

Claim 1

IN A TELEPHONE SYSTEM, A CENTRAL OFFICE, A PBX WITH A PLURALITY OF STATIONS EACH EQUIPPED WITH CONTROL SIGNALING MEANS CONSISTING OF A DIAL AND A HOOKSWITCH, A PLURALITY OF TRUNK LINES CONNECTING SAID PBX WITH SAID CENTRAL OFFICE, SAID PBX STATIONS COMPRISING FIRST AND SECOND GROUPS WHICH ARE AND ARE NOT, RESPECTIVELY, RESTRICTED FROM MAKING OUTGOING CELLS FROM SAID PBX, SUBSCRIBER LINES CONNECTED TO SAID CENTRAL OFFICE, SWITCHING CIRCUITS IN SAID CENTRAL OFFICE FOR COMPLETING TRANSMISSION CONNECTIONS BETWEEN SAID SUBSCRIBER LINES AND SAID TRUNK LINES, COMMON INDICATOR MEANS AT SAID PBX FOR INDICATING AN INCOMING CALL ON ANY ONE OF SAID TRUNK LINES, MEANS FOR ANY ONE OF SAID PBX STATIONS TO BE CONNECTED WITH THE PARTICULAR TRUNK LINE HAVING AN INCOMING CALL IN RESPONSE TO THE DIALING OF A PREDETERMINED CODE AT SAID PBX STATION, AND MEANS SUBSEQUENTLY RESPONSIVE TO ADDITIONAL CONTROL SIGNALS FROM SAID ONE OF SAID PBX STATIONS FOR COUPLING ANOTHER ONE OF SAID PBX STATIONS TO SAID PARTICULAR TRUNK LINE.