Minot Phone book 1958 #4

Rural Line Ringing Code – 1958 – Phone subscribers on the same rural line could call each other. The process was to dial the code 18 and then the 4^th and 5^th digit of the called party’s number, in the order given. After dialing the proper sequence of numbers you would replace the receiver on the hook and allow time for the called party to answer. After waiting a short period of time you would pick up the receiver and hopefully the party you called would be there. Example of a ringing code: 4^th Digit –2 and  5^th digit 4 the ringing code was 1S – 1L – 2S (S being a short ring and L being a long ring)