[Silver Fox Phil]

I remember the old medicine bottle with tea in it, as you say with a cork stopper! Forgot all about that. My dad worked on the railways as a parcels delivery driver. (Later to become National Carriers Ltd.) in Market Rasen, then moved to Lincoln followed by a move to Peterborough. He knew many a local footplate crew and also had free rail passes for our family. So it was I used to go with him to work during our school holidays and met his many mates. They had the bottles of tea, just as you described. Happy memories.
Cheers
Phil