letters sent by a private friend in his way, journey or travel, to be delivered by him to the person to whom they are directed, without hire, reward or other profit or advantage for receiving, carrying or delivering them;

letters solely concerning the affairs of the sender or receiver thereof, sent by a messenger on purpose; and

letters solely concerning goods or property, sent either by sea or by land to be delivered with the goods or property which the letters concern, without hire, reward or other profit or advantage for receiving, carrying or delivering them:

Provided that nothing in this section shall authorise any person to make a collection of letters excepted as aforesaid for the purpose of sending them otherwise than by post.

(2)

For the purposes of this section and section 5, the expression "letters " includes postcards.