Out of curiosity, do you remember why you didn't just call or send a letter? I have zero familiarity with what it was like to send a telegram, but I imagine even 40 years ago it would be more difficult to send a telegram then a letter or phone call.
40 years ago telegrams were as obsolete for most communication as they are today, sending them was (as it is now [0]) largely a way of saying “this message is important enough for me to pay an exorbitant fee to have physical media remotely produced and hand delivered”.
