“Dear Martin,
A line saying that I am now in Waterloo Station 4 -pm. Letter will follow.
Alf.”
Half penny stamp. Not cheap, then. And the picture on the front is a coloured print of St Paul’s Cathedral’s ‘choir & reredos’.
Who was Alf? Did you know him? Was he a cousin, maybe even your dad? He was confident it seems that his postcard would arrive at Fern Street on the same day. And maybe a letter too. Postal services were frequent but postcards always had priority over letters so they arrived more quickly.
This is the equivalent of our modern day text message or Tweet.
THE GREAT FERN STREET POSTCARD MYSTERY 
The King George V “Profile” halfpenny postage stamp was in use between 1912 and 1918. In 1918 the postcard rate double to 1d!
So was Alf at Waterloo Station (which serves the south coast) en route to the battlefields of France and Belgium?
Alf evidently survived WWI, because he is mentioned in Postcard#1, postmarked 1943. He could be Martin’s brother, Fred (1894 – 1985), but he could just as easily be a friend or work colleague – another part of the mystery :)